Why do some human traits, such as height and hair color, show a large number of phenotypes?

The theories on the expansion of galaxies maybe re-examined to strengthen science should not be tested to strengthen science will weaken scientific knowledge if they change will become laws if they don't change

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

Whats one way that rocks do not follow the typical rock cycle pathway?