A rule or principle that describes what happens in nature is called a law.

Why was the sample heated in step 5? describe the chemical principles involved in the reasoning behind this step?

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

Guard cells control which event? the growth of plants capture of solar energy gas exchange in leaves water absorption in roots