Which of the following hypotheses is written correctly?* 1.If I heat up a tennis ball it will bounce high.
2.Frozen tennis balls will not bounce as high because they are more dense.
3.If a tennis ball is frozen, it won't bounce as high as one that is not frozen.
4.If I freeze a tennis ball, then it will not bounce as high because the ball is more dense.

Aballoon is rising vertically upwards at a velocity of 10m/s. when it is at a height of 45m from the ground, a parachute bails out from it. after 3s he opens his parachute and decelerates ata a constant rate 5m/s.when. (a) what was the height of the parachutist above the ground when he opened his parachute? (b)how far is the parachutist from the balloon at t=3s? (c)with what velocity does the parachutist hit the ground? (d)after how long does the parachutist hit the ground after his exist from the balloon?