4-3. Determine the constant k such that f (x) = -kx2, −2 ≤ x ≤ 2;

0 elsewhere is a probability density function. Then find:

(a) The cumulative distribution function

(b) P(X > 1/2)

(c) P(X ≤ 1)

(d) P(−1 ≤ X ≤ 1)