This one is hard

[Clutch306]

Four particles, each of mass 0.200kg, are placed at the vertices of a square with sides of length 0.500m. The particles are connected by rods of negligible masses. This rigid body can rotate in a vertical plane about a horizontal axis that passes through one of the particles (A for example, as shown in figure attached.)
(a) What is the rotational inertia I of the body about axis A?
(b) What is the net torque Tnet about axis A (due to the gravitational forces), when the rod AB is horizontal?
(c) What is the angular acceleration a of the body at the instant rod AB is horizontal?

[enigma]

Others have said it in your other threads, but you must show what you've tried, Clutch.

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