Assignment:
A projectile is launched from a platform 20 feet high with an initial velocity of 112 feet per second, The height h of the projectile at t seconds after launch is given h= - 16t^2 + 112t +20 feet.
a. How many seconds after launch does the projectile attain maximum height?
b. What is the maximum height?
Provide complete and step by step solution for the question and show calculations and use formulas.