Answer: cofactors.
Explanation:
Epinephrine, insulin and auxins are cofactors.
Cofactors are non protein substance which activate enzymes activity by increasing the rate of chemical reaction of enzymes. They are organic molecules and they assist in enzyme activity. They exist in performing some reactions the enzymes cannot perform alone.
For example, insulin activate enzyme hexokinase which phosphorylate glucose.
Velocity can vary as long there is specific direction (displacement)
Speed has no direction therefore change in speed is not necessary the velocity...
Velocity is also in a specified direction
it's A. urine hope it helped
