Can you guys name all the koalas species

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

Isotopes of the same element have differ in their

During binary fission, what events must occur before the cell splits into two new cells?