use separation of variable method to solve

0.6) A rectangular membrane {LxH l, fixed at all sides, with zero initial conditions, subjected to external constant force ho. Find the motion f you can place force on either side, it does not matter) 0.7) a drum of radius a fixed at outer side, given zero initial conditions, subjected to external force in the form of husinw find the motion of the drum?you can place force on either side, it does not matter) OS) A disk of radius a, given zero temperature at the outer edge, given initiall temperature T4 find temperature distribution