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Air Pollution The amount of nitrogen dioxide, a brown gas that impairs breathing, present in the atmosphere on a certain May day in the city of Long Beach is approximated by 134 A(t)=2+30 (0 sts 11) 1 + 0.3(r a) where AU) is measured in pollutant standard index (PSI) and t is measured in hours, with t : 0 corresponding to 7 A.M. Determine the time of day when the pollution is at its highest level. time time Select- Select 7 A.M. 8 A.M. Subn 9 A.M. 10 A.M. 11 A.M. 12 P.M. 1 P.M. 2 P.M. 3 P.M. 4 P.M. 5 P.M. 6 PM. 7 P.M.Textbooks. A textbook company estimates that the weeklyr marginal cost associated with producing x textbooks is em = 10.84 - 0.0016x If the weekly xed cost of producing textbooks is 668 (this means C(O) = 668), find an expression for C(X), the weekly cost of producing X textbooks. C(X) =