Answer:
The toy's maximum height is
.
Step-by-step explanation:
The equation that models the toy's height in feet from the ground at t seconds after he threw it is given by :
.....(1)
It is required to find the toy's maximum height. For maxima or minima, put

Plugging the value of t in above equation,

Now put t = 1.75 s in equation (1) such that,

So, the toy's maximum height is
.