given the jointly PDF function as: fyy(xy)=0.05 [u(x)-u(x-5)] [uy)-u(y-4)], the value of the E[Y] is a. none of these b. 5. . 2 d. 0. Two random variables X and Y have a joint probability density function given by fXY(x, y) = Kxy, 0 < x < 2,0 < y < 2, and 0 otherwise, then the value of K is a. 1/2 b. 1 c. 1/4 d. 1/3 The joint nth order central moment of X and Y random variables are a. The mean of X if n = k = 1 b.The variance of X if n 2, and k = 0 c. Zero if n = k = 0 . d.The central mean of X if n = k = 1