Why wouldn’t you travel higher

Which part of cellular respiration must occur before any of the other steps can occur

What is the next step in muscle contraction after the actin changes shape? (apex)

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