Each year at a college, there is a tradition of having a hoop rolling competition. Alex rolls his 0.250 kg hoop down the course. If the hoop has a radius of 50.0 cm, what is the moment of inertia of Alex's rolling hoop? 0.0625 kg ⋅ m2

0.125 kg ⋅ m2

12.5 kg ⋅ m2

625 kg ⋅ m2

Abatter hits a 0.140-kg baseball that was approaching him at 30 m/s and, as a result, the ball leaves the bat at 40 m/s in the reverse of its original direction. the ball remains in contact with the bat for 2.0 ms. what is the magnitude of the average force exerted by the bat on the ball?