Problem # 6 ( 20 points ) - Joint pdf And calf Suppose that the joint pdf for two random variables & and Y is given by f ( 20 9 ) = A ( 20 + 9 ) 2 e - ( 2 + 2) for ( a , y ) in the first quadrant and zero everywhere else and 1 is a positive constant a . ) ( 3 points ) Determine the value of A b . ) ( 6 points ) Determine the caf function F ( 20 , y ) C . ) ( 6 points ) Determine the marginal pats for ( 20 ) and for ( y ) 1 . ) ( 3 points ) Determine E ( X ) , E ( ) and E ( XY e . ) ( 2 points ) Are X and Y independent ? Explain