Eighteen students from four different classes- three freshmen, four sophomores, five juniors and six seniors have applied for membership in their school's Communication Board, a group that oversees the college's newspaper and radio show. Eight pcxsitions are open. The selection is done at randorn. (a) What is the probability that each class gets two representatives in the Board? (b) What is the probability that at most two senior students are selected in the Board? (c) Given that the first two selected students are from senior class, what is the proba- bility that at least two freshmen are selected in the Board?