What is the probability that the student plans to go to medical school?

Assume that the class consists of 45 percent freshmen, 5 percent sophomores, 40 percent juniors, and 10 percent seniors. Assume further that 45 percent of the freshmen, 40 percent of the sophomores, 20 percent of the juniors, and 30 percent of the seniors plan to go to medical school. One student is selected at random from the class.(1) What is the probability that the student plans to go to medical school?(2) If the student plans to go to medical school, what is the probability that he is a junior?