How to estimate the average rate of change of a modeling function from a graph  Khan Academy  Summary and Q&A
TL;DR
Teresa's height decreases at a varying rate as time progresses, with a significant decrease when she deploys the parachute.
Questions & Answers
Q: What is the initial height of Teresa when she jumps?
Teresa's height is 700 meters when she first jumps from the plane.
Q: How does Teresa's rate of height decline change with time?
As time progresses, Teresa's rate of height decline becomes faster until she deploys the parachute. After deploying the parachute, her rate of decline slows down.
Q: What is Teresa's height at 3 seconds and 8 seconds after the jump?
At 3 seconds, Teresa's height is approximately 650 meters, and at 8 seconds, her height is approximately 375 meters.
Q: What is the average rate of change in Teresa's height between 3 seconds and 8 seconds?
The average rate of change in Teresa's height between 3 seconds and 8 seconds is approximately 55 meters per second, indicating a decrease in height.
Summary & Key Takeaways

Teresa's height starts at 700 meters and decreases over time.

The rate of decline in her height becomes steeper as time progresses until she deploys the parachute.

After deploying the parachute, her rate of decline slows down.