The distance , in kilometers, that a car travels at a speed of 80 km per hour, for hours, is given by the equation .

1. If the car has gone 120 kilometers, how long has it been traveling?
2. Rewrite the equation to represent time, , as a function of distance, .

Match each function to its inverse.

Functions and are inverses. When is -10, the value of  is 7, or .

1. What is the value of ?

2. Determine if each point is on the graph of , on the graph of , or neither. Explain your reasoning.

Crickets make chirping sounds by rubbing their wings together. The number of chirps they make is closely related to the temperature of their environment. When the temperature is between 55 and 100 degrees Fahrenheit, we can tell the temperature by counting the number of chirps!

A formula that is commonly used to find the temperature in degrees Fahrenheit is:

• Count the number of chirps in 14 seconds.
• Add 40 to get the temperature.

Let be the number of chirps that crickets make in 14 seconds and be the temperature in degrees Fahrenheit.

1. What is the temperature when a cricket chirps 52 times in 14 seconds?
2. Write an equation that defines as a function of .
3. How many chirps would we expect to hear in 14 seconds when it is 60 degrees Fahrenheit?
4. Write an equation that defines as a function of .

The parking rate, , in dollars for a car in a garage is a function of , the hours it is parked.

Image of daily parking rates at College and Lakeview parking garage. 0 to 2 hours, free. 2 to 2 point 5 hours, 2 dollars. 2 point 5 to 3 hours, 3 dollars. 3 to 3 point 5 hours, 4 dollars. 3 point 5 to 4 hours, 5 dollars. 4 to 5 hours, 6 dollars. 5 to 6 hours, 7 dollars. 6 to 7 hours, 8 dollars. More than 7 hours, 8 dollars. Lost ticket, 8 dollars.

1. Find .
2. Find .
3. Find .