Question

A ball is projected upward at time t=0.0s, from a point on a roof 90m above the ground. The ball rises, then falls and strikes the ground. The initial velocity of the ball is 37.0m/s if air resistance is negligible. The time when the ball strikes the ground is closest to

Answer 1

as v becomes zero at the highest point, i prefer considering different travelling directions so it will become less complicated.
dont forget to add the total time up .

also to master the skills, write down the "uvsat" may help (thats the way i found it easier to handle problems)