What occurs during periods of adaptive radiation

Providing immunity by injecting the body with a weakened form a pathogen is known as

Variety of living organisms; includes genetic, species, and ecological types.

Johnny rode his bike 4 blicks down the street to his friend's house once he got to his friend house and realized he could not cone out to play he turned aroubd and went back home. what is 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