Suppose that the joint p.d.f. of a pair of random variables (X, Y) is constant on the

Question:

Suppose that the joint p.d.f. of a pair of random variables (X, Y) is constant on the rectangle where 0 ≤ x ≤ 2 and 0 ≤ y ≤ 1, and suppose that the p.d.f. is 0 off of this rectangle.
a. Find the constant value of the p.d.f. on the rectangle.
b. Find Pr(X ≥ Y).