1 (12 marks) Let and have joint pdf: (, ) = 12(1 ) for 0 < < 1, 0 < < 1 (a) Show all working to demonstrate that (4 marks): () = 6(1 ) for 0 < < 1 and () = 2 for 0 < < 1 (b) Find the covariance of and using (, ) = [] [][] and determine whether and are independent, orthogonal, or uncorrelated (8 marks)