A car was at a 30km marker and began to drive. The car passed a 90km marker and the time had changed 30 minutes. What was the average speed of the car? Show your work.

Which features on mars point to the possibility of liquid water on the planet? impact craters with sharp rims volcanic cones with craters gullies and stream-like channels mountain ranges with faults

There are two-speed cameras, one in an are where the speed limit is 30 km/h and another where the speed limit is 50 km/h. in which will there be a smaller time interval between the photographs? explain your answer.

Describe how the motion of a spring being pushed forward and backward is similar to the motion of air particles in a sound wave.