The median weight of a boy whose age is between 0 and 36 months can be approximated by the function w(t) =7.61 + 1.11t-0.0088t2 + 0.000003+3, where t is measured in months and w is measured in pounds. Use this approximation to find 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' (t) = 1.11 -0.0176t + 0.000009t b) The weight of the baby at age 7 months. The approximate weight of the baby at age 7 months is |Ibs. (Round to two decimal places as needed.)