Solve the all given parts of following problem:
Problem: A ball is thrown vertically upwards with an initial velocity of 16.20 m/s, from the ground.
Part I: How long is the ball in the air?
Part II: What is the greatest height reached by the ball?
Part III: Calculate the time at which the ascending ball reaches a height of 11.2 m above the ground.
Any help I can get on this problem is greatly appreciated! I'm not too familiar with this problem.