the brain mass of a fetus can be estimated using the total mass of the fetus by the function b=0.22m^0.87, where mis the mass of the fetus (in grams). Suppose the brai mass of the 20-g fetus is chnaging at a rate of 0.23 g per day. Use this to estimate the rate of chnage of the total mass of the fetus dm/dt

dm/dt= __g per day