0.87 The brain mass of a fetus can be estimated using the total mass of the fetus by the function b = 0.22m ,where m is the mass of the fetus (in grams) and b is the brain mass (in grams). Suppose dm the brain mass of a 20-g fetus is changing at a rate of 0.28 g per day. Use this to estimate the rate of change of the total mass of the fetus, F' dm er da dt 9 P Y (Round to five decimal places as needed.)