posted by seanso .
A ball is thrown vertically upward with a speed of +10.0 m/s.
(a) How high does it rise?
(b) How long does it take to reach its highest point?
(c) How long does the ball take to hit the ground after it reaches its highest point?
(d) What is its velocity when it returns to the level from which it started?
Someone will be glad to critique your thinking. For using conservation of energy for the first question.
For (b), require that the ball decelerate at rate g until the vertical velocity is zero.