Answer: 
Step-by-step explanation:
Given the following Quadratic equation:

The steps to solve it are:
1. Substitute
into the equation:

2. Use the Quadratic formula
.
In this case:

Substituting values into the Quadratic equation, you get (Round the values to the nearest hundreth):

3. The positive value is the time that the rocket will hit the ground.
Therefore, the rocket will hit the ground after
.