6.101 Suppose that a box contains 25 light bulbs, of which 20 are good and the other 5 are defective. Consider randomly selecting three bulbs without replacement. Let E denote the event that the first bulb selected is good, F be the event that the second bulb is good, and G represent the event that the third bulb selected is good.

a. What is PsEd?

b. What is PsFuEd?

c. What is PsGuE > Fd?

d. What is the probability that all three selected bulbs are good?