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You are to take a multiple-choice exam consisting of 100 questions with five possible responses to...

You are to take a multiple-choice exam consisting of 100 questions with five possible responses to each. Suppose that you have not studied and so must guess (select one of the five answers in a completely random fashion) on each question. Let r.v. X represent the number of correct responses on the exam.

  1. (a). Specify the probability distribution of X.

  2. (b. What is your expected number of correct responses?

  3. (c). What are the values of the variance and standard deviation of X?

  4. (d). What is the probability that you will get exactly the expected number of correct responses?

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