9. A student takes a 5 - question, multiple-choice exam with four choices for each question and guesses on each question. n = p = q = a) Find the probability of guessing exactly 2 out of 5 correctly. P (X = 2) = b) Find the probability of guessing at most 2 out of 5 correctly. P (at most 2) = ce that the random variable X is defined as the number of tails