Please help and i need steps to understand fully

2. Let X be a random variable with the following probability mass function: X = X 0 1 2 3 P(X = x) 0.10 0.20 0.30 0.40 (a) Find P( X 2 2 ) . (b ) Find P(X 2 2 X 2 1). (c) Find E(X). (d) Find Var(X). 3. If you roll a pair of fair dice, what is the probability of I (a) getting a sum of 1? ( b ) getting a sum of 5? (c) getting a sum of 12