Suppose the average daily metabolic rate for certain types of animals can be expressed as a function of mass by r = 147.2m 0.5, where m is the mass of the animal (in kilograms) and r is the metabolic rate (in kcal per day). a. If the mass of an animal is changing at a rate of dm dt, find dr dt. b. Determine dr dt for a 230−kg animal that is gaining mass at a rate of 4 kg per day. a. If the mass of an animal is changing at a rate of dm dt, find dr dt. dr dt =