QUESTION 5 Determine the unique solution of the following differential equation by using Laplace transforms: y"+4y=3H(t-4) The initial values of the equation are y(0) = 1 and y'(0) = 0. QUESTION 6 Determine the current i in the circuit where +6. +13i = 0 if i(0) = 24 and i' (0) = 4, di di dt dt by using Laplace transforms. QUESTION 7 The motion of a mass on a spring is described by the differential equation x = 0 and d x dt [9] dx -= 0, at t= 0 find the steady state solution for x(t) and discuss the motion. dt [8] +100 x 36 cos8t. If [11]