need help understanding these two questions.

Some years ago it was estimated that the demand for steel approximately satised the equation p = 351 - 30K. and the total cost of producing x units of steel was ct!) = 200 + 51):. {The quantity 1:: was measured in milions of tons and the price and total cost were measured in millions of dollars.) Determine the level of production and the corresponding price that maximize the prots The maximum prot occurs at x = (million tons). The median weight of a boy whose age is between 0 and 36 months can be approximated by the function w(t) = 9.58 + 1.46t - 0.001 1t~ + 0.000427+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) and b) below. . . . . . a) 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.)