A square weightless frame ABCD with the side a is rotating around the side AB with the constant angular velocity ω1. A uniform disk of radius R and mass m is rotating around the frame’s diagonal AC with the constant angular velocity ω2. The center of the disk coincides with the center of the frame. Assuming ω1 = ω2 = ω find

a. The kinetic energy of the system.
b. The magnitude of the torque that needs to be applied to the axis AB to keep it (the axis AB) still.