Question 4: A discrete-time system has a transfer function: H(z)= 2 4z 2 Calculate the output y(n), if the input is the unit-function x(n) = n. Question 5: Solve the following difference equation, the initial values are all zeros: y[k+2] 0.3y[k +1]+0.02y[k] = (0.01)(0.3)* u[k] Question 6: Find the transfer function of the following discrete systems: y(k)+2y(k-1)-y(k-2) = 2x(k)-x(k-1)+2x(k-2)