A 520-kg projectile is fired at an angle of 300 degrees

Question

Compute all parts of given problem:

Problem: A 52.0-kg projectile is fired at an angle of 30.0 degrees above the horizontal with an initial speed of 1.24 x 10² m/s from the top of a cliff 150 m above level ground, where the ground is taken to be y = 0.

Part A: What is the initial total mechanical energy of the projectile?

Part B: Suppose the projectile is traveling 87.9 m/s at its maximum height of y = 310 m. How much work has been done on the projectile by air friction?

Part C: What is the speed of the projectile immediately before it hits the ground if air friction does one and a half times as much work on the projectile when it is going down as it did when it was going up?

I need help to determine the initial total mechanical energy of the projectile.