A projectile is launched at t = 0 with initial speed vi at an angle q above

Question:

A projectile is launched at t = 0 with initial speed vi at an angle q above the horizontal.
(a) What are v x and v y at the projectile's highest point?
(b) Find the time t at which the projectile reaches its maximum height.
(c) Show that the maximum height H of the projectile is