here is the question:

Given an urn U that contains 4 red, 3 blue and 2 green balls. We draw 3 balls from U without replacement. What are the probabilities for (a) 3 red balls. (b) 2 blue balls and one green ball. (c) 1 ball of each color. Hint: First, consider all possible combinations for the case that we can distinguish the balls of the same color. Then, use Laplace probabilities to find the solution