Which describes how light travels? A. about 300,000 km/second
B. fast
C. in a straight line
D. all of the above

In a closed system, the total energy prior to an energy transformation is the total energy after. a. equal to b. unrelated to c. greater than d. less than

What happens to light waves from a star as the star moves away from earth?

Acaterpillar tries to climb straight up a wall a meter high, but for every 2 cm up it climbs, it slides down 1 cm. eventually, it reaches the top. when it reaches the top, it does not pull itself over so it will slide down 1 cm. what is the total displacement traveled?