The marginal external cost associated with air pollution increases with the annual output of a polluting industry. At the current competitive equilibrium level of output per year, the marginal external cost is $10 per unit of output. To achieve efficiency, a. a corrective tax of $10 per unit of output is required.
b. a corrective tax of more than $10 per unit of output is required.
c. a corrective tax of less than $10 per unit of output is required.
d. a corrective subsidy of $10 per unit of output is required.
e. a corrective subsidy of less than $10 per unit of output is required .

The answer is "Option c".

Explanation:

The Marginal external cost, owing only to the production of an extra unit of goods or services, is the cost changes for persons besides the producer or buyer of goods or services. In this, question the  "option c" is right in, this regard because it needs a correction tax of less than $10 per unit of production.

a manufacturer of printed circuit boards uses exponential smoothing with trend to forecast monthly demand of its product. at the end of december, the company wishes to forecast sales for january. the estimate of trend through november has been 200 additional boards sold per month. average sales have been around 1000 units per month. the demand for december was 1100 units. the company uses α = 0.20 and β = 0.10. make a forecast including trend for the month of january.

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