Please answer 16 points !!

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

As an asteroid comes close to earth, it's name will change to? apex

How many autosomes are in this human karyotype? how many sex chromosomes?