A woman drops a rock from a bridge to the water 17.5 m below. with what speed does the rock strike the water? a. 0 m/s
b. 18.5 m/s
c. 171m/s
d. 9.8 m/s
e. 17.5 m/s

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.