Carli's class built some solar-powered robots. They raced the robots in the parking lot of the school. The graphs below are all line segments that show the distance, d in meters, that each of three robots traveled after t seconds.

a. each graph had a point labeled. What does the point tell you about how far that robot has traveled?

b. Carli said that the ratio between the number of seconds each robot travels and the number of meters it has traveled is constant. Is she correct? Explain.

c. How fast is each robot traveling? How did you compute this form the graph?