11 Chapter 11: Delivering Your Speech; Using Language

Lauren Rome, College of the Canyons

Adapted by William Kelvin, Professor of Communication Studies, Florida SouthWestern State College


After reading this chapter, you should be able to:

  • compare and contrast the four methods of speech delivery and when to use them.
  • explain ways to engage audiences in online settings.
  • explain how the physical setting of a speech affects delivery.
  • identify key elements in preparing to deliver a speech.
  • assemble some tips and strategies for common speaking situations.

Dr. Martin Luther King Jr.

Figure 11.1: Dr. Martin Luther King Jr.1


If you’re like most people, you probably aren’t afraid of the preparation involved in giving a speech. Instead, you’re more likely anxious about delivering your actual speech to an audience. The irony, of course, is that your speech delivery is actually the shortest aspect of the entire process. You will spend much more time (days, at least) researching, compiling, and practicing your speech, while the actual delivery will be somewhere between five and ten minutes.

Let’s look at this hypothetical scenario about two public speaking students, Sasha and Andres. Sasha spends weeks researching, outlining, and crafting her speech. When it comes to delivering her speech, she is conversational and engaging but messes up a couple of times when trying to remember her oral citations. Although Sasha thinks this has ruined her speech, the audience thinks her speech was informative and interesting. Audiences are less apt to notice little mistakes in a speech, and if they did, they would most likely blame any imperfections on a case of nerves.

On the other hand, Andres does not spend as much time preparing and relies on the fact that he is comfortable in front of a crowd and good at “winging it.” Although the audience might consider him to be entertaining, they might also find themselves unable to recall any substantial information delivered in the speech. They might also drift off and stop focusing due to disorganization in Andres’s speech.

The moral of the story is clear: a well-prepared speech delivered with flaws is still a well-prepared and significant speech, but a speech poorly prepared yet delivered flawlessly, is still a poorly prepared and insignificant speech.

We do realize students feel the most anxiety about delivering their speech. This chapter is designed to help you achieve the best delivery possible and eliminate some of the nervousness you might be feeling. In this chapter, we are going to examine best practices for delivering speeches in multiple situations.

Methods of Delivery

Speeches are categorized into four broad methods of delivery, depending on the amount of preparation required and the nature of the occasion. We aim to acquaint you with these four methods of delivery, and how you focus your time on the preparation, practice, and presentation of extemporaneous speeches.

Manuscript Speaking

Manuscript speaking is the word-for-word iteration of a written message. You might be familiar with manuscript-style speeches if you have ever heard a State of the Union Address given by a president, or if you watch cable news anchors deliver the news. In each of these cases, the choice to use a manuscript is made because the exact words matter, and much time and energy are expended on getting everything just right.

There are costs involved in manuscript speaking. If you are not experienced in using them, your presentation will likely sound robotic and disengaging. Additionally, if you are reliant upon a manuscript to convey your points, your focus will be on the script itself instead of making eye contact with the audience. If you speak from a manuscript, you do not “see” your audience; therefore, you are not receiving their messages and cannot react appropriately. Most likely, unless you’re running for president, or you’re in an oral interpretation class, you won’t use this method. This method is used in public statements when people are concerned about lawsuits, for example making a public apology while hoping to forestall future trials, or wanting to demonstrate contrition immediately, without necessarily admitting guilt.

Memorized Speaking

When you were in elementary school, did you ever have to memorize a poem or a part of a speech? If you are like most students, the answer is “Yes.” There is nothing wrong with memorization. But if you try to memorize an entire speech, you risk forgetting what you planned to say and coming across as completely unprepared.

Memorized speaking is when a speaker commits their entire speech to memory. Although it might be tempting to do this, it is not expected of you in an introductory public speaking course. Memorization is a significant time commitment and there are many risks associated with this method. Often, when attempting to memorize speech content, there is potential to overlook verbal and nonverbal elements of delivery. Will you also memorize which gestures you use, or when you pause? What about the tone or pitch used to make your voice sound engaging? If these are missed, you might remember to say all the right words, but your audience will be bored. Memorized speeches can sound as robotic as manuscript speaking when executed unartfully. Selecting words in advance removes something human from delivery and damages the connection to the audience.

The greatest risk of memorization, though, is forgetting your words. If you go completely blank during the presentation, it will be extremely difficult to find your place and keep going. Sometimes people use this method when note cards would look amateurish, and, like manuscript delivery, when every word counts, for example a tightly timed speaking contest.

Impromptu Speaking

Impromptu speaking is when a speech is delivered with little to no advanced preparation. This might sound intimidating, but impromptu speeches are not usually as long and detailed as the assigned speeches you’re preparing in a public speaking class. Likely, you’ve already given many impromptu speeches throughout your life. For example, if you’ve ever had to introduce yourself to a class at the beginning of the semester, or had to explain to your parents why you’re late for curfew you’ve definitely given an impromptu speech before. It’s what you use when you raise your hand to answer a question in class.

Overall, Impromptu speaking is the most common speech you’ll give. It’s also a very valuable skill. Imagine being asked to explain your perspective during a board meeting or speaking up about a new rule change suggestion at a school district meeting. Being able to swiftly form cogent verbal utterances can make you stand out from the crowd and enhance your political savvy.

Extemporaneous Speaking

Extemporaneous speaking means that you’ve had plenty of time to research, prepare and rehearse. If you’ve made it this far in the textbook, then you’re probably in a public speaking class and developing a speech to extemporaneously deliver to your class. The goal of extemporaneous delivery is not to memorize your speech word for word, but to know the general content and then speak conversationally using brief notes to help keep you on track.

Speaking extemporaneously has many advantages. First, it allows you to connect with your audience, which promotes the likelihood that they will perceive you as knowledgeable and credible. In addition, your audience will pay attention to the message because it is engaging both verbally and nonverbally. The disadvantage of extemporaneous speaking is that it requires a great deal of preparation for both the verbal and the nonverbal components of the speech. If you think back to the scenario in our introduction with Sasha and Andres, such preparation cannot be achieved the day before your speech.

Since extemporaneous speaking is the style used in the great majority of public speaking situations, most of the information in this chapter is targeted to this kind of speaking.

Understanding the Speaking Situation

Depending on the situation in which you are speaking, many elements are likely to change. For example, giving a speech in a college classroom is going to be different from presenting at work, or giving your toast as maid of honor or best man. In each of these scenarios, there are things you must take into account to deliver your speech effectively. These elements might include the location, room and audience size, or furniture and equipment.

Delivering to a Virtual Audience

Photo of computer screen with Zoom showing

Figure 11.2: Zoom Classroom2

Whether in an online class, a virtual interview, or a virtual meeting with your team, knowing how to present information online is a necessary skill for the modern world. Although you aren’t always able to see your entire audience at any given time, they will usually be able to see you! Mary Abbajay in Forbes (2020) provides some tips for a successful virtual presentation:

  • Get the Lighting Right: As a presenter, it is essential that people can see you well. Make sure you have good lighting in front of your face. If your back is to a window, close the shades. While natural light is often the best choice, if your workspace doesn’t have natural light and you do a lot of virtual presentations, consider purchasing supplemental lighting to enhance your image. Ring lights are popular choices for providing balanced lighting; they can be used with desktop computers or cell phones.
  • Choose the Right Background: To prep your video conferencing space, clean it. Avoid a cluttered background or anything that can be distracting. Use tasteful decorations and avoid anything potentially embarrassing or controversial. Next, consider masking your space. Learn whether your presentation platform enables you to use virtual backgrounds or blur your background, as Zoom allows.
  • Know the Technology: A dry run is essential so that you’re comfortable with the platform features. Make sure you practice with the same technical setup (computer and internet connection) that you will use when you deliver the presentation. Ask a friend to help you to see if your equipment works well on their end.
  • Play to the Camera: When you are the one speaking, look directly into your computer’s camera, not on the screen or at the other participants. This takes some practice, but it makes the viewer feel as if you are looking right at them. Some presenters turn off their self-view so that they aren’t distracted by their own image. Put the camera at eye level. Try not to have your camera too far above or below you. If it’s too low, then you run the risk of creating a double chin. And to the audience, this makes it appear as though you are looking down toward the desk or floor! A camera too high makes it difficult to maintain eye contact, as you may find your gaze dropping as you speak.
  • Get Close (But Not Too Close): You want the camera to frame your face, shoulders, and waist. Check with your professor about specific requirements. People are drawn to faces, so you don’t want to lose that connection by being too far away, but you also don’t want your face to take over the whole screen like a disembodied head because, well, that looks weird. Practice your positioning and distance.
  • Stand Up: Standing up provides a higher energy level and forces us to put our bodies in a more presentation-like mode. Standing up mirrors a typical live speaking situation, which is more professional.
  • Do A Sound Check: If your sound is garbled, people will tune out (and your instructor won’t be able to grade your speech!). While people may forgive less than perfect videos, if they can’t hear you, they miss your message. Practice with someone on the other end of the presentation platform. Make sure your sound emits clearly. Sometimes headphones or external microphones work better than computer audio, sometimes not. Every platform is different, so make sure your sound quality is excellent every time.
  • Plug into Your Modem: If possible, plug your computer directly into your modem using an ethernet cable. This will give you the strongest signal and most stable internet connection. The last thing you want to happen during your presentation is to have a weak or unstable internet signal.
  • Be Yourself and Have Fun: Again, just like in face-to-face presentations, audiences connect to authenticity, so be yourself! Let your personality show through. Have fun. If you look like you’re enjoying the presentation, so will others. Happy people retain information better than bored or disinterested people, so model the energy that you want to create. The audience takes its cue from you.

Delivering to a Live Audience: Physical Spaces and Audiences

Physical spaces with live, in-person audiences have different variables that need to be considered than virtual spaces. The size of the room or location where the speech is delivered and the size of the audience might change elements of our delivery.

Auditorium with audience

Figure 11.3: Auditorium 3

Since this is a public speaking textbook for a college class, you might already be familiar with the location of the speeches you will be giving. All classrooms are not created equal, though. Some classes can be small and quaint, while others are held in lecture halls that hold hundreds of people. Depending on where you will be speaking, let’s look at some important considerations:

  • How large is the space I will be speaking in? Do I need a microphone?
  • If I am not using a microphone, how loud will I need to speak so everyone can hear me?
  • How is the space configured? Where do I need to stand so my audience can see me clearly?
  • How will movement enhance my connection to the audience?
  • What furniture and equipment might I need to use or navigate?

Furniture and Equipment

Some classrooms, lecture halls, conference rooms, or stages may have furniture or equipment that can be used to support a speaker’s delivery. Although this is not an exhaustive list, the two most common apparatuses are briefly discussed below: lecterns and microphones.


Although these seemingly antiquated stands might make your presentation feel more formal, they can be used to the speaker’s advantage. Lecterns are a great place to set your notes so you can gesture freely, or move around to engage with the audience. Also, if you are worried about what to do with your hands, it could be a nice place to rest them. Just be careful to check in on how you are resting them; it is all too tempting to grip the edges of the lectern with both hands for security. You also don’t want to use lecterns as a physical crutch and lean on them. Lecterns can keep you rooted in one place, thus deterring movement. They can also be a barrier between you and the audience. Yes, that barrier may feel protective, but building rapport is the name of the public speaking game. The most polished speakers usually do not rely on lecterns, and many instructors disallow their use, so ask your instructor for their policy, and see if you can break away from them, or keep them to one side of the room.

Student in a white dress giving a speech

Figure 11.4: Student Speech4


If the setting is large enough, you might need to use a microphone to help project your voice. While this isn’t a frequent occurrence for beginning speakers, it could be something you encounter. Microphones require preparation and adaptation. If a microphone is too close or far from your mouth, it could distort or drop your voice. Some microphones only pick up your voice if you speak directly into them. The best plan, of course, would be to have access to the microphone for practice ahead of the speaking date. Most often you will encounter fixed microphones that are stationary. You may need to adjust its positioning, if possible. However, you may also find yourself using lavalier microphones, which are clipped on your clothing near your face, and may have a bulky communication pack that clips to your waistline. Practicing with these lav mics is especially important, because they impede your movement a bit and can feel awkward. Another mic issue to watch out for is so-called “hot mics,” which catch people saying embarrassing things. Always assume microphones are on!

Preparing for Your Speech Delivery

Now with a better understanding of the variables of the speaking situation, you can begin thinking about your actual speech delivery. Although this book has spent a lot of time on the structure and content of your speech, those will fall flat if you forget to consider your verbal and nonverbal delivery.

Consider Verbal and Nonverbal Elements

Sometimes it isn’t what you say, but how you say it that matters in public speaking. Although you will spend a considerable amount of time writing and organizing the content of your speech, those words could fall flat if you don’t consider the verbal and nonverbal elements that can help them come alive. Vocal variety, the use of multiple delivery elements at once, helps to keep your delivery engaging and your audience connected.

Vocal Elements

  • Pronunciation: The conventional patterns of speech used to form a word. If you are not familiar with how to pronounce a word, look it up. If you can’t find it, find a way to confidently pronounce the word that you will remember; you don’t want to tell the audience you don’t know how to pronounce it or stumble through the word.
  • Enunciation: How clearly the speaker pronounces words. If you’ve ever had to ask someone to repeat a word, they may suffer from poor enunciation.
  • Articulation: Using your mouth, tongue, and airflow as the instrument to produce sound. Whether you say “tomato or tomahto” is the difference in articulation.
  • Volume: The loudness or softness of a speaker’s voice. Controlling your volume ensures your audience can hear you clearly, adds variety, and brings attention to the most important moments in the speech.
  • Pitch: The highness or lowness of a speaker’s voice. A voice that lacks variety in pitch can be described as monotone, which causes people to lose interest. We all have a natural range of pitch; attempt to vary your delivery along that spectrum. A change of pitch outside of your normal range can be attention-getting.
  • Rate: How quickly or slowly you speak. Controlling your rate can be one of the most challenging things a speaker has to do. When nerves kick in, it can be really hard to slow the speed that you’re talking, since you likely just want to “get this over with.” When a speaker’s rate is too quick, the audience has a hard time following along. Further, it can make the speaker look nervous, damaging their ethos.
  • Flow of Delivery: The consistency of delivery. Is the delivery smooth or is it disrupted with a start-stop style? The goal is to have a smooth delivery.
  • Pause: A break in speaking. Never underestimate the power of the pause. It can focus the audience’s attention or create anticipation. Hot tip – pauses give you time to think about what you’re going to say. Embrace the pause! A silent pause is much more engaging and relaxing for the audience than vocalized pauses.
  • Vocalized Pauses: Words or sounds such as, “um,” “like,” “ya know,” or “uh.” These can take the place of an actual word or silent pause. Instead of filler words, use that moment to pause for a breath and collect your thoughts.
  • Energy and Enthusiasm: All verbal and vocal elements are enhanced by giving the delivery energy and enthusiasm because it provides voice inflection which is a change in tonality. The more excited we are during the delivery, the more engaged the audience will be, up to a point. It is rare, but it is possible to overdo it. Keep the audience, topic and situation in mind when planning your level of enthusiasm.

Nonverbal Elements

  • Eye Contact: Using your eyes to directly connect with your audience. Eye contact lets your audience feel that you are speaking directly to them. It is the fastest, and easiest, way to create a relationship with your audience. This is the single most powerful nonverbal element of your delivery.
  • Gestures: Motions with your hands or arms. You do not want to talk too much with your hands, but you do not want to stand like a statue either. Controlled body language and variety in gestures help to reinforce your points and help the audience interpret the impact of your words. Some things to think about: what will yo udo with your hands when you’re not gesturing? Most instructors do not want you to put your hands in your pockets. How will you handle your note cards? Perhaps you can pass them from one hand to the other so that you can gesture with both hands at times, or at times keep them hidden in one hand to gesture with both simultaneously.
  • Facial Expressions: How your eyes and mouth work to display the “emotional tone” of a message. Direct eye contact and smiling when appropriate, or not smiling when appropriate, will help the audience understand your message. Your face tells a story. Does it match your speech?
  • Physical Appearance: To have the best impact on an audience, you also need to think about your clothing and appearance basics. You don’t need to run and buy expensive new clothes, but you do need to think about the impression your appearance might make. If you want to be taken seriously, you must present yourself seriously. Keep in mind that your goal is to have your audience focus on your face rather than an article of clothing or your uncombed hair. You do not want to be too revealing in your choice of clothing because it is a distraction. Some advice: wear what makes you feel most confident, and make sure the outfit is professional and fits the occasion. Some professors may suggest informal professional dress such as khaki pants and a collared shirt. Other professors may encourage formal professional dress such as slacks and a collared, button-up shirt. This is a good time to discuss dress with your professor.While in this moment you may be worried about your final grade, think beyond that outcome. Do you want to develop comfort speaking formally? If you want to go into a field where formal wear is the norm, you should start performing in such garments as soon as possible. Consider going to a thrift store. Even if the clothes are worn, they will have the cut and weight that you must become accustomed to. The formal wear made ubiquitous by Western customs tend to make speakers hot and sweaty—sad, but true! Your public speaking class presents you the chance to practice in a low-stakes environment, so that you will feel comfortable in formal wear for job interviews, sales pitches, etc.

Student giving Commencement Speech

Figure 11.5: Commencement Speech5

Practicing Your Speech

Have you heard the saying “practice makes perfect”? Well, forget it. Perfection is not a realistic goal. Instead, you should aim to be prepared, which is exactly what practice will give you. Try this new phrase: “practice makes better.” What do you think? You might think that the purpose of practicing is to memorize the words written in your outline, but this isn’t true. Usually, you aren’t graded on whether or not you say the words exactly as they are written in your outline. Instead, practice lets you get comfortable with the content and find areas for improvement. It’s simple: more practice means less anxiety and better delivery. Let’s look at some strategies for practicing your speeches so you can feel more confident in your delivery.

Imitate the Speaking Situation

If you recall earlier in this chapter, the speaking situation is the setting, location, or platform in which you might be giving your speech. When practicing, it is ideal for you to get familiar with the speaking situation before you give your presentation. If you are speaking in a conference room or a classroom, it’s necessary to understand how loud you need to project your voice, or how the room might affect your ability to make eye contact with your audience. If possible, visit the space (or a similar space) ahead of your speaking engagement. Even if your speech is not written yet, it’s always wise to learn the room and become more comfortable with it. Examine the physical features, technology, lighting, etc. You don’t want to be shocked if you wind up under a bright light! One of your authors visited a public speaking venue where he was set to perform and got comfortable, then when the performance day came, the venue had removed the lectern! You never know what will happen, but preparation will likely never hurt.

Additionally, if you only read your speech in your head, or whisper the words quietly to yourself, you aren’t actually practicing for a public speech. Practicing your speech in the way in which you will deliver (stand up, speak out loud, use eye contact, etc.) helps you get more comfortable with the content and whether you tend to mispronounce or stumble over words. Also, sentences on paper do not always translate well to the spoken medium. Practicing out loud allows you to actually hear where your sentences and phrases are awkward, unnatural, or too long, and allows you to correct them before getting up in front of the audience. Practice saying the speech differently every time. As you do, the ideas become more your own, and you worry less about sticking to an idealized script. When your mind has more potential pathways to follow in the moment, you are less likely to get stuck.

The more similar you can make the practice setting to the speaking setting, the more prepared you will be. You don’t want the first time you are delivering your speech to be when you are delivering your speech to the entire audience.

Also, practice in clothes that are similar tow hat you will wear in your speech, or the exact outfit, if it’s convenient. You may find that it does not fit well or irritates you. One experience you do not want, is to be preparing to leave the house on the day of your speech and find out that your pants will not close, your blouse is missing a button, or the tag of your undershirt is nagging you.

Get Feedback from Others

Speaking publicly is a challenging task (even for the authors!). It’s not easy to do alone. Seeking useful, constructive feedback from your classmates, peers, or family can make the difference between a good speech and a great speech. By practicing your speech in front of others, they can share their opinion on your language choices, verbal and nonverbal elements, and timing.

One thing you have to ask of your observers: be honest. They can’t just tell you, “That was great!” since that doesn’t tell you what was great. It might help to give them specific questions to answer:

  • How was my eye contact?
  • Could you hear me?
  • Was my voice engaging or monotone?
  • Did I mispronounce any words?
  • How was my posture?
  • Were my gestures effective?
  • Did I have any mannerisms or distracting habits that I should try to avoid?

Record Yourself Delivering Your Speech

We know this feels “cringey,” but a video recording can help you identify elements of your speech content and delivery that another observer might not. Are you concerned about what you do with your hands when you speak? Or whether your voice is as powerful as you planned? Or how many vocalized pauses do you use? A video recording allows you to be the audience member of your own speech and is invaluable in creating the overall presentation you want.

Another idea is to make an audio recording of your speech and listen to it on the go–in the car, on the train, while you brush your teeth. This process will cause you to memorize the order of information, and also remember some turns of phrase. You can even try recording different versions where you vary your citation style, word choice, etc. Just as Hollywood sceeen-tests scenes to see which audiences respond best to, you can evaluation your options and decide which performative choices you think best.

Tips for Effective Delivery

Prateek Kalakuntla speaking to a crowd

Figure 11.6: Prateek Kalakuntla6

Know your material. You should know the information so well you do not have to devote your mental energy to the task of remembering the sequence of ideas and words.

Prepare well and rehearse enough so you don’t have to rely heavily on notes. Many speakers, no matter how well prepared, need at least a few notes to deliver their message. Even your professors use lecture slides or outlines to help keep them on track! If you can speak effectively without notes, by all means, do so. But if you choose to use notes, they should be only a delivery outline or keyword outline. Notes are not a substitute for preparation and practice. Refer to assignment instructions for rules about note cards. Many professors only allow 3-by-5 inch note cards on firm card stock–not typical 8.5-by-11 inch paper nor regular-weight printer paper.

Establish a personal bond with listeners. Begin by selecting one person and talking to them personally. Maintain eye contact with the person long enough to establish a visual bond (about five to ten seconds). This is usually the equivalent of a sentence or a thought. Then shift your gaze to another person. In a small group, this is relatively easy to do. But, if you are addressing hundreds or thousands of people, it is impossible. What you can do is pick out one or two individuals in each section of the room and establish personal bonds. Then, each listener will get the impression you are talking directly to them. As your speech progresses, try to build more personal bonds with more audience members.

Monitor visual feedback. While you are talking, your listeners are responding with their nonverbal messages, such as head nods, wrinkled or furrowed brows, wide eyes, or even tears. Use your eyes to actively seek out this valuable feedback. If individuals aren’t looking at you, they may not be listening either. Make sure they can hear you. Consider moving towards them and work to actively engage them.

Additionally, if you look out at your audience and you notice that someone has a confused expression on their face, that is a signal that something you’ve said is unclear. There is nothing wrong with stopping and rephrasing what you are saying. After all, your speech is for the audience and their understanding. Monitoring visual feedback helps you as a speaker and helps you to be seen as a more credible speaker.


Good delivery is meant to support your speech and help convey your information to the audience. Anything that has the potential to distract your audience means that fewer people will be informed, persuaded, or entertained by what you have said. Practicing your speech in an environment that closely resembles the actual situation that you will be speaking in will better prepare you for what to do and how to deliver your speech when it counts.

Remember, whether you are presenting in person or virtually, all presentations are audience-centered. Their time is valuable, so honor that time by delivering the best presentation you can. No matter what kind of presentation you are giving, you must find ways to create authentic audience connection, engagement, and value.

Reflection Questions

  • After having reviewed the methods of delivery, how do you see extemporaneous speaking as an effective tool you can use in the classroom or in a career?
  • If you are delivering a speech virtually, what aspects of your speaking area and technology do you attend to in order to maximize your performance?
  • After reading about vocal, verbal, and nonverbal elements of delivery, how will you improve your own delivery?
  • What will be your specific method of practicing for your speeches? Who can you practice in front of? Will you record your speech and watch it back to evaluate the delivery?

Key Terms



Extemporaneous Speaking

Eye Contact

Facial Expression

Flow of Delivery


Impromptu Speaking

Manuscript Speaking

Memorized Speaking





Vocalized Pause



Abbajay, M. (2020, April 20). Best practices for virtual presentations: 15 expert tips that work for everyone. Forbes. Retrieved April 15, 2022, from https://www.forbes.com/sites/maryabbajay/2020/04/20/best-practices-for-virtual-presentations-15-expert-tips-that-work-for-everyone/


1 Photo by National Parks Service is licensed under CC BY 2.0
2 Photo by Sanskar Dahal is licensed under CC BY-SA 4.0
3 Photo by Navneet Sharma is licensed under CC BY-SA 4.0
4 Photo by Mattbuck is licensed under CC BY-SA 2.0
5 Photo by Gerald R. Ford School of Public Policy University of Michigan is licensed under CC BY-ND 2.0
6 Photo by Clear UNT is licensed under CC BY-NC-ND 2.0


Introduction to Public Speaking Copyright © by Jamie C. Votraw, M.A.; Katharine O'Connor, Ph.D.; and William F. Kelvin, Ph.D.. All Rights Reserved.

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