Do anyone know this ?

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

Easy 6th grade work! 100 points! i need fast! compare the parts of a cell and the cell as a whole to another common nonliving system (i.e., a car, a city, describe the parts of a cell and their primary function.

An infection of the pulp and the surrounding tissue in the mouth is called