Suppose that a certain college class contains 42 students. Of these, 23 are freshmen, 28 are history majors, and 8 are neither. A student is selected at random from the class.
(a) What is the probability that the student is both a freshman and a history major?
(b) Given that the student selected is a freshman, what is the probability that he is also a history major? Write your responses as fractions.