plz solve these questions

What is a transfer function? What is a first order transfer function? For a motor actuating a spinning disk with moment of inertia J and viscous friction D, Newton's laws give the following ordinary differential equation (ODE): Jx(t) + Dx(t) = k_m u(t) where x is the angular velocity of the disk, u is the motor torque, and k_m is the motor constant. (a) Assuming that the output y is the angular velocity of the disk, derive the transfer function Y (s)/U(s). (b) A general form of a first order transfer function is given below: Y(s)/U(s) = K/Ts + 1 where K is the steady-state gain, and tau is the time constant, which is the time it takes to reach 1-1/e of the final value (about 63%). Using your answer from part (a.), find K and tau in terms of J, D, km