Compute all parts of given problem:
Problem: A football kicker can give the ball an initial speed of 24 m/s. He is 45 m from the goalpost which has a crossbar 2.69 m high.
Part A: What is the smallest angle of elevation that he can kick the football and score a field goal?
Part B: What is the largest angle of elevation that he can kick the football and score a field goal?
This is a physic problem, reply as soon as possible. Thank you.