When you use a lever to lift a heavy boulder, A) the energy the lever exerts on the boulder is greater than the energy you exert on the lever (B) the force the lever exerts on the boulder is greater than the force you exert on the lever (C) the force the lever exerts on the boulder is less than the force you exert onthe lever (D) none of these.

The gravitational force exerted by the earth on the moon (A)is =to the gravitational force exerted by the moon on earth (B) is greater than the gravitational force exerted by the moon on earth (C) is inversely proportional to the masses of the earth and the moon (D) is directly proportional to the distance between them.

what happens to the gravitational force between 2 objects if the mass of 1 object is quadrupled? the gravitational force is: (A)quadrupled (B)increased 16 times (C) reduced by 1/4 (D) none of these