A test has multiple choice questions, with four choices of answers from which to choose. After reading the first four questions, you realize you have no idea what any of the correct answers are. Assume you randomly guess at the answers for all four questions.

a. What is the probability that you answered the first question correctly?

b. What is the probability that you answered the first two questions correctly?

c. What is the probability that you answered the first three questions correctly?

d. What is the probability that you answered all four questions correctly?

e. What assumption are you making with these calculations?