I think the answer would be 70
Answer:
Part a)

Part b)

Part c)

Explanation:
Part a)
Moment of inertia of the system about an axis passing through B and C is given as




Part b)
Moment of inertia of the system about an axis passing through A and C is given as




Part c)
Moment of inertia of the system about an axis passing through the center of the square and perpendicular to the plane of the square



