A bag contains three red, seven black and five green marbles.Four marbles are selected at random without replacement.

Question 1(2 points)

What is the probabity that all four marbles are black?

Question 2(3 points)

Find the probablity that no more than 2 green marbles are chosen.

Question 3(2 points)

What is the probablity that exactly 2 marbles are green and none are red?

Question 4(3 points)

What is the expected number of red, black and green marbles?