The median weight of a boy whose age is between 0 and 36 months can be approximated by the function w(t) = 3.19 + 1.51t - 0.0050t2 + 000040713, where t is measured in months and w is measured in pounds. Use this approximation to nd the following for a boy with median weight in parts a] through c) below. a) The rate of change of weight with respect to time. W'U) = b) The weight of the baby at age 13 months. The approximate weight of the baby at age 13 months is El lbs. (Round to two decimal places as needed.) c) The rate of change of the baby's weight with respect to time at age 13 months. The rate of change for the baby's weight with respect to time at age 13 months is approximately lbslmonth. (Round to two decimal places as needed.)