In a second semester English class, 30% of the students are sophomores and the rest freshmen; 25% of the sophomores are repeating the course and 15% of the freshmen gained admission to the course by advanced placement. The professor randomly selects a student to comment on the assignment. (a) Find the probability that the professor selects a sophomore who is repeating the course. (b) Find the probability that the professor selects a freshman who gained advanced placement admission to the class.