A projectile has an initial upward speed of 1000 feet per second which is steadily decreased by gravity at the rate of 32.2 feet per second per second, so that the upward speed at a subsequent time t is dy/dt = 1000 - 32.2t ft/sec. If the initial position of the projectile is 200 ft above ground, what is the maximum heght that the projectile will attain?

A. 18,874 ft

B. 15,728 ft

C. 22,648 ft

D. 13,107 ft

The answer for this is letter B however I dont know its solution. Please provide me solution through handwritten form for better understanding. thank you