1. A car is traveling at a constant speed of 60 miles per hour. How far does the car travel in:

   1. 2 hours?
   2. 5 hours?
   3. hours?
2. Create a representation that shows the relationship between the elapsed time and the distance traveled for this car.

A traffic safety engineer was studying traffic patterns. She set up a camera to record the speed and direction of cars and trucks that passed by. She decided to represent positions to the east of the camera with positive numbers and positions to the west of the camera with negative numbers.

Number line. To the left is the word west. To the right is the word east. The numbers negative 50 through 50, in increments of 10, are indicated. There are tick marks midway between.

1. A car is traveling east at 12 meters per second. Where will it be 10 seconds after it passes the camera?

2. A car is traveling west at -14 meters per second. Where will it be 10 seconds after it passes the camera?

3. Complete the table to show the position of each vehicle after traveling at a constant velocity for the given amount of time.

   	velocity (meters per second)	time after passing the camera (seconds)	position (meters)	equation
   car A	+12	+10	+120
   car B	-14	+10
   car C	+9	+5
   car D	-11	+8
   car E	-15	+20
   car F	+8	0

4. Complete the sentences. Be prepared to explain your reasoning.

   • A positive number times a positive number equals a _______________________.

   • A negative number times a positive number equals a _______________________.

1. If there are 400,000 cars in a city, about how much carbon dioxide is released by these cars in one year?
2. If there are 10,000 clams in a clam bed, about how much carbon is released by this clam bed in one year?
3. If a park has 25 pine trees and 10 oak trees, about how much carbon dioxide is released by these trees in one year?
4. If the city with 400,000 cars wanted to absorb as much carbon dioxide as was released by all these cars each year, how many parks and clam beds of these sizes would they need?
5. College students in the Netherlands developed a car that releases -2 kilograms of carbon dioxide per year. If half of the cars in the city were this new type of car, how much carbon dioxide would be released by all the cars in the city in one year?