Answer:
1)The rocket hit the ground at 
2)The maximum height of the rocket = 12.468 feet
Step-by-step explanation:
<u><em>Step(i):-</em></u>
Given equation
y = -2 x² + 5 x + 7 ...(i)
Differentiating equation (i) with respective to 'x' , we get

Equating zero

⇒ -4 x +5 =0
⇒ -4 x = -5
⇒
<em> The rocket hit the ground at </em>
<em></em>
<u><em>Step(ii):</em></u>-
...(ii)
Again differentiating equation (ii) with respective to 'x' , we get

The maximum height at x = 
y = -2 x² + 5 x + 7



<em>The maximum height of the rocket = 12.468 feet</em>