Answer:

Explanation:
we know that
The height of Justin’s rocket is modeled by the equation

This is the equation of a vertical parabola open downward
The vertex is a maximum
where
The coefficient of t^2 represent the acceleration 

The coefficient of t represent the initial velocity 

The constant of the equation represent the initial height 

Remember that
 Elena launched his rocket from the same position, but with an initial velocity double that of Justin’s
so
Now the initial velocity is 

substitute 
The height of Elena’s rocket is the equation
