Answer: position E
Step-by-step explanation:
After the ball is thrown it has a negative acceleration (it's slowing down) at a rate of 9.8 m/s2 (round that to 10 m/s2), which is g, the rate of acceleration due to gravity. The position of the ball is shown every 1 second. At position B, the ball has a speed of 40 m/s, at C = 30 m/s, at D = 20 m/s, and at E = 10 m/s. Every 1 second, the ball slows down by 10 m/s. At F, the top, the instantaneous speed = 0 m/s. Then the ball will then speed up by 10 m/s every second, until it reaches K, where the speed is back at 50 m/s.