### Home > PC3 > Chapter 12 > Lesson 12.1.2 > Problem12-33

12-33.

A ball is thrown off the top of a building and lands on the ground below. The function $h(t) = -16t^2 + 64t + 48$ gives the ball’s height in feet with respect to time in seconds.

1. How long will the ball be in the air?

This is basically asking when the ball will hit the ground.
What is the height of the ball when it is on the ground?

2. Make a table of the function using $1$-second increments. Use the table to sketch a graph of the function over the interval that fits this situation.

3. Calculate the average velocity for each $1$-second time interval that the ball is in the air.

Recall that average rate of change is just the slope between two points.

4. What is happening to the average velocity of the ball with respect to the time?

5. What does the average velocity tell you about the change in position of the ball?