Amy counts the wave crests traveling down a stretched string. five wave crests pass amy in two seconds. what is the frequency of the wave?
a. 5.0 hz
b. 2.5 hz
c. 10 hz
d. 2.0 hz

Imagine that someone pushes one marble toward a motionless marble. would there still be action-reaction forces involved in the collision? how might the marbles’ motions be changed? ?

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

The combining of light nuclei is called blank. blank as in not actually blank. you know what im tryin to say.