To determine the amplitude of a wave, you would need to know the . a) distance from the crest to the trough. b) maximum displacement of the wave from the equilibrium position. c) number of cycles in a given period of time. d) the distance from the crest of one wave to the crest of the next wave.

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.