describe how a bell jar model could be used to demonstrate breathing in humans

Me with these questions if you’re it sure don’t answer

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

Brainliest ! which would require more force to move or slow down between a bowling ball and a soccer ball? explain why?