Astudent who is trying to write a paper for a course has a choice of two topics, a and b. if topic a is chosen, the student will order two books through interlibrary loan, whereas if topic b is chosen, the student will order four books. the student believes that a good paper necessitates receiving and using at least half the books ordered for either topic chosen. if the probability that a book ordered through interlibrary loan actually arrives in time is .9 and books arrive independently of one another, which topic should the student choose to maximize the probability of writing a good paper? what if the arrival probability is only .5 instead of .9?