If you pushed someone down a hard flight of stairs, would they die?

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

What causes darkening of the skin as melanin production increases

Agroup of students are walking in the park and one of them takes a picture of a pollen grain that is been blown by the wind what caption can the student use for this picture