When jim was exercising his heart rate went from 70 beats to 98 beats per min. what was his percent increase

The answer is 28 as an increase in heart rate. Subtract 98 from 70 and get 28.

i think it would be b the increase in body temp

fluid balance is an aspect of the homeostasis of organisms in which the amount of water in the organism needs to be controlled, via osmoregulation and behavior, such that the concentrations of electrolytes (salts in solution) in the various body fluids are kept within healthy ranges. the core principle of fluid balance is that the amount of water lost from the body must equal the amount of water taken in.