A group of students took an exam, and their grades and class are summarized below.

A B C Total

Freshman 20 19 14 53

Sophomore 4 7 12 23

Total 24 26 26 76

If one student is chosen at random, find the following probabilities. Give each answer as a fraction, or round it to 3 places after the decimal point, if necessary.

(a) Find the probability that the student got a 'B' or is a freshman.

(b) Find the probability that the student was a sophomore given they got a 'C'.