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Researchers are concerned about the prevalence of hypertension among a population of elderly patients at a cardiovascular clinic aged 45-60. Suppose the prevalence of hypertension in the group is actually quite high at 38%. Assume that a sample of 14 participants is collected. Use a binomial distribution to solve for the following. a) What is the expected number of participants in this age range to report hypertension? (1 point)[16a] (Example answer #.##)   b) What is the probability associated with finding 7 responses indicating hypertension? (1 point)[16b] (Example answer .####)   c) What is the probability associated with finding between 5 and 8 responses indicating hypertension? (1 point)[16c] (Example answer .####) (hint x is 6 and 7)

HIV/AIDS patients are regularly monitored for their CD4 counts in order to make sure that antiretroviral therapies are effective. Suppose the distribution of CD4 counts in a population is approximately normal with µ=299 and σ=45. a) HIV patients are defined as moving into the AIDS stage of their disease course after their CD4 counts are ≤ 200. What proportion of patients in this population is suffering from an AIDS diagnoses? (1 point)[15a] (Example answer .####)  b) HIV positive patients maintaining a CD4 count over 400 can frequently carry on regular lives with complications mostly limited to medication side effects. What proportion of patients in this population is considered healthy? (1 point)[15b] (Example answer .####)

Suppose we want to sample a neighborhood for a community needs assessment. The neighborhood has 9 subdivisions and 4 of the 9 are to be collected for household sampling. How many different ways can we select these households? (1 point)

Find the area of the shaded region. The graph depicts the standard normal distribution with a mean of 0 and a standard deviation of 1.  

1. x is the 2nd digit of your UFID.  2. If you think there is a mistake in problem statement, please write down your assumption, and solve your problem based on your assumption.  3. Make sure your handwriting is recognizable. 4. Please show your work step by step (similar as how I did in example problems in class). We will grade your work by checking your understanding of each step. Having correct final answer without steps showing us how won’t get any points for the problem. Of course, if the correct answer is because of cheating, then it’s DSO’s decision on how to deal with it.  5. Show all your work on paper from the first page to the last page using webcam before you exit Honorlock. Once you exit Honorlock, you cannot change anything on your paper.  6. Submit your work on “Exam 1 submission” as a single pdf file.  7. Both Honorlock “Exam 1” and “Exam 1 submission” will be available for everyone start from 6:55 pm to 11:05 pm. a.  For majority students without extra time allowed, please finish this exam within 2 hours and submit it on “Exam 1 submission” before 9:05 pm. b.  For students with 50% extra time allowed, please finish this exam within 3 hours and submit it on “Exam 1 submission” before 10:05 pm. c.  For students with 100% extra time allowed, please finish this exam within 4 hours and submit it on “Exam 1 submission” before 11:05 pm.   Late submission is allowed with penalty. For every one minute late, there will be 2 points off.  For students with extra time allowed, please put your extra time allowed in the comment when you submit.  9. This is a close-book, close-note exam. Make sure you don’t have textbook, lecture notes, or homework solutions around you.  10. Do not use Chegg or any other similar website. Any violation in exam will be reported to Dean of Students Office directly. Based on our experience, a lot of times online solutions are wrong and we figured out students using online solutions because their answer were wrong in a weird way. You should definitely trust yourself better than those “Chegg expert”. 

For the pin at C, it’s considered as failure when shear stress reaches (400+x) ksi. Calculate the diameter of the pin if safety factor is 3.  Please type the pin diameter in the box below. 

stunt person jumps from the roof of a tall building, but no injury occurs because the person lands on a large, air-filled bag. Which one of the following best describes why no injury occurs?

A 0.2-kg steel ball is dropped straight down onto a hard, horizontal floor and bounces straight up. The ball’s speed just before and just after impact with the floor is 10 m/s. Determine the magnitude of the impulse delivered to the floor by the steel ball.

A pebble rolls off the roof of Science Hall and falls vertically. Just before it reaches the ground, the pebble’s speed is 17 m/s. Neglect air resistance and determine the height of Science Hall

At time t = 0 s, a puck is sliding on a horizontal table with a velocity 3.60 m/s, 35.0° above the +x axis. As the puck slides, a constant acceleration acts on it that has the following components: ax = –0.360 m/s2 and ay = –0.980 m/s2 . What is the velocity of the puck at time t = 1.50 s?