1. A die id rolled twice. Determine the probability that the sum of the two rolls is grater than 6, given that the firstroll is a 4.

2. A jar contains six red marbles and four green ones. If two marbles are drawn at random form the jar, and the firstmarble is not return to the jar, find the probability of each of these events:

a) the second marble is green, given that the first is red

b) both marbles are red

c) both marbles are green

d) the second marble is red