What do we call a cell that is very picky about what it lets in or out of itself ? (Give evidence)

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

In a vegetable garden 45 bean plants have been eaten by deer 5 are untouched what is the frequency of bean plants in the garden that have been eaten?

Need with these questions . need the answers in a rush for these questions are the answers i put down are correct or not? ?