At a certain college, 15% of the students received an A in their required math course, 10% received an A in their required Chemistry course, 5% received an A in both. A student is selected at random.

a.) What is the probability tha he receieved an A in either Chemistry or Math?

b.) What is the probability that he received an A in Chemistry, if he had an A in math?

c.) What is the probability that he receieved an A in math, if he had an A in chemistry?

d.) Are the events "A in math" and "A in chemistry" independent? Explain.