2. (5pts) Suppose a student is taking a multiple choice test that has 10 questions, each with possible choices A, B, C, D, or E, and only one of which is correct. If the student simply guesses at each question: a) Find the probability that he gets at least 3 questions correct. b) The number of correct questions he should expect to get correct. c) Would it be unusual for the student to get 5 correct answers by guessing? Explain