Does anybody know these ?

Four types of motile cells in human body?

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

Based on the topographic map of mt. st. helens, what is the contour interval of the volcano about height is 2,950 m?