Two objects are exerting a gravitational force of F on each other. The mass of each object is doubled and the distance is changed to 4r. What is the value of the new gravitational force? A)
16 F

B)
F/2

C)
F/4

D)
F/16

E)
4 F

Emmy kicks a soccer ball up at an angle of 45° over a level field. she watches the ball's trajectory and notices that it lands, two seconds after being kicked, about 20 m away to the north. assume that air resistance is negligible, and plot the horizontal and vertical components of the ball's velocity as a function of time. consider only the time that the ball is in the air, after being kicked but before landing. take "north" and "up" as the positive ‑ and ‑directions, respectively, and use ≈10 m/s2 for the downward acceleration due to gravity.