Think of the composition of each layer of Earth and their relative sizes. Also consider Earth's atmosphere, its oceans, its ice caps, and other materials on its surface. Think about how large or small these parts of Earth are compared to one another.

Johnny rode his bike to a friend's house 4 blocks down the street in his neighborhood. he immediately rode back home once he realized his friend was not able to play. what was his displacement for the total bike ride? how did you determine this? what could we use as a reference point to determine he was in motion during his bike ride? why can you use it as a reference point