A If X and Y are independent and identically distributed exp

A.) If X and Y are independent and identically distributed exponential variables with parameter =3, compute each of the following joint densities. U=4X+Y, V=5X/(X+Y). fU,V(u,v)= B.) If X and Y are independent and identically distributed uniform random variables on (0,1), compute each of the following joint densities. U=5X+Y, V=2X/(X+Y). fU,V(u,v)=