If a tax is levied on the sellers of a product, then the demand curve will

The optimal output of a collective consumption good is found by_____

a. equaling marginal cost and the vertical summation of all individual's demand curves b. equaling price and marginal cost c. equaling marginal cost and the horizontal summation of all individual's demand curves d. equaling marginal cost and long-run average total cost

Your parents have given you a new car on your 16th birthday for which they paid about $24,000. Assume this is also the price you would get if you decided to sell the car a month after getting it. The monthly costs of driving the car are $100 for oil changes and $200 for gas. If you decide to keep the car, the total costs of the car to you this month will be

A. $2,300. B. $24,300. C. $300. D. $0.