detailed solution

E. For each of the following, determine whether it can serve as the probability distribution of a random variable X. Explain your answer. 1. P(X) = 1 for x = 1, 2, 3, . . ., 8 8 2. P(X) = - for x = 1, 2, 3, . . .,9 6 3. P(X) 3+x for x = 1, 2, 3, 4 3 -X 4. P(X) = 12 for x = 1, 2, 3, 4 25x 5. P(X) = X-2 for x = 1, 2, 3, 4, 5 5