Question

A ball is thrown upward from the ground at a tower with a speed of 20 m/s there is window in the tower at height of 15 m/s from the ground

Answer 1

The initial speed = u.
The height = 80m
Time interval = 6 seconds
Time of ascend, t10=u-gt1Time of descend, t2u=gt2So, t1+t2 =62u/g = 6u = 3g=29.4 m/s

Answer 2

100÷264+557-556+766-688/I 7+76