How much is the relative velocity of two car moving along a straight path with same velocity

This is the substance(s) formed in a chemical reaction.

Agroup of students were investigating the force of gravity. they began by dropping a foam ball from a height of 3 meters into a bucket of sand. the ball hit the sand in 0.306 seconds. they dropped additional balls of approximately the same diameter, but of different masses. here is the data they collected. based on this experiment and the collected data, what would their conclusion be?

Which of the following list the divisions of the geologic time scale in order from longest to shortest