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Consider an advertising monopolist that faces a market demand function P(Q.B) =690 -0.50 + 8 " and has the separable cost function C(Q.B) = 150 + B, where O is the units of production and B is the units of advertising. The units of advertising have been scaled so that they have a constant cost of $1 per unit, The profil lunelion is: c(0,B) = (890 -0.50 + 8 5) 0-150-B. What is the profil-maximizing units of advertising, B? OA. 037875.0 O B. 727812.5 OC. 592312.5 XD. 410062.5 FE. 455625.0