Answer:
Explanation:
Given
h varies as

Above h represents the height of object at any instant t
For example at t=0
h=190 ft
At t=1 s
h=-16+64+190=238 ft
For maximum height differentiate h w.r.t time

Put
to get maximum height

t=2 i.e. at t= 2 s h is maximum
h at t=2 s
