A] Sketch the following expression (simplest method, for x(at-b), shift x(t) by b, then scale the resulting function) x(t) u(2t- 1)-u(-2t +4) B] For the following function, state why it is periodic, and find its period x(t) cos(3rt+1) sin(7rt-2) C] Evaluate the following integral I 2e-3) cos(7(x-5))8(x-3) d 0