There are ten Cortland, seven Gala and eight Macintosh apples in a basket. You pick

three apples from the basket.
a) What is the probability that three picked apples are all Gala or all Macintosh?
b) What is the probability that three picked apples are one Gala and two Macintosh?
c) What is the probability that three picked apples are one Cortland, one Gala and one
Macintosh?
d) Develop a probability distribution X for the number of Gala apples picked
plzz help