P-R intervals measures time during what

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

Asap i will reward you brainliest for best which sentence about protists is accurate? all protists are unicellular and microscopic in nature. they have organelles, so protists are eukaryotic in nature. all protists make their own energy through photosynthesis.

Ecology can best be described as the study of what