How to solve these four questions of cumulative distribution functions?

1.

A certain discrete random variable X has a discrete probability distribution with P1 = P(X = 1) = 7: P2 = P(X = 2) = P3 = P(X = 3) = PA = P(X = 4) = 1 4 0,47 0,3 0.2 0.1 0 0 1 2 3 4 Then the associated cumulative distribution function given by F(x) = P(X 4) ? It is X iv) What is P(4