PLEASE HELP WILL MARK BRAINLEST!!!

Describe the primary and secondary immune response in terms of speed and number of antibodies produced?

Which statement correctly describes a way that mutations increase the likelihood that a species will survive in a changing environment

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