What is the Precambrian time A) 4 billion years between the first eon and the last won B) the first won C) the last eon D) the first three eons

What does homeostasis means in biology?

Which blood cell spend most of their time in the lymphatic system?

Johnny rode his bike 4 blicks down the street to his friend's house once he got to his friend house and realized he could not cone out to play he turned aroubd and went back home.what is 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