1. In one of the design assignment, you are given the overall response, H(z) of 4- cascaded systems as listed below, where H(z) = H (2)H2(z)H3(z)H4(z). H (2) = 5az-2 H3 (2) = 1 1+1.5az-1 H2(z) = 1+0.5az-1 1+0.2az-1 H4(2) = 1 1+0.8az-1 Here, a takes the value of the last number in your student ID. Notes: If the last number of your ID is zero, take the 2nd last number. If your 2nd last number is zero, take the 3rd last number. a. Draw the block diagram of a cascaded realisation for H(z). [10 marks] b. Determine the difference equation describing the system. [10 marks) c. If the input, x[n] = 0.5"u[n] + 28[n 1] + 28[n 2), determine the expression for Yelw). [10 marks)