Consider the following experiment: There are five red balls and three white balls in a box. An experiment consist of drawing three balls in succession. Once a ball is drawn, it is not replaced.

a. What is the probability that two or more red balls will be obtained in the three draws?

b. What is the probability that exactly two white balls and one red ball will be obtained in the three draws?

c. Given a white ball is selected on the first draw, what is the probability of selecting two white balls and one red ball after the three draws?