question B) A moment of inertia can be thought of as how much torque it takes to rotate things, similar to how an object's mass is related to how much force we need to accelerate it. Why is it 'harder' to rotate an object when it has a larger radius from the axis of rotation? (Usually the fundamental reason for things in physics is because of energy, so you should answer this by considering how the radius of a rotating object relates to its kinetic energy)