First find out how many more inches it needs to grow, 54-37.5; It needs to grow 16.5 more inches. If it grows 3 inches a year then you have to do 16.5/3; 5.5. It will take 5.5 or 5 1/2 more years to grow to 54 inches.
I don't know this but I will say C.
Answer:
Using their equation and the fact that the ball will fall 3 ft before reaching the ground:
3 = 16 t^2 + 50 t + 3 represents the given situation
16 t^2 + 50 t = t (16 t + 50) = 0
16 t + 50 = 0
t = 50 / 16 = 3.12 sec