Answer:
400 ft
Step-by-step explanation:
H = 160t - 16t^2 = 16t(10 - t)
The minimum/maximum of a quadratic function is always exactly in between the 0 points (or any other points with equal value, as a parabole is symmetrical).
Let's solve for H = 0
16t(10-t) = 0
t = 0 or 10 - t = 0
t1 = 0, t2 = 10
the maximum is at (t1+t2)/2 = 5
H(5) = 16*5(10-5) = 80*5 = 400
