Which of the following is true about gravity? check all that apply.  a. two objects experience a greater gravitational pull when they are closer together.  b. gravity causes objects in free fall to fall with constant velocity toward the center of the earth.  c. the force of gravity is greater for objects with more mass.  d. gravity is a natural force that causes pairs of objects to be pulled together.

jupiter is the largest planet in our solar system, having a mass and radius that are respectively, 318 and 11.2 times that of earth. suppose that an object falls from rest near the surface of each planet and that the acceleration due to gravity remains constant during the fall. each object falls the same distance before striking the ground. determine the ratio of the time of fall on jupiter to that on earth.