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The production of paper towel in a perfectly competitive market can be represented by the inverse supply curve P = 40, where Q is millions of packs produced per month. The inverse demand for paper towel is P = 10 - 60. If the production of paper towel causes an external marginal cost of $0.50 per pack, the socially optimal price of paper towel is _ and the socially optimal quantity is _ million. 0 a. $4.30; 0.95 O b. $4.20; 1.05 O c. $4; 1 0 cl. $3;2