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 .

Employees at a library check out books to patrons. books have an isbn and a name. the library sometimes has multiple copies of the same book. books have one or more authors. a patron is an individual who has an active (non-expired) library card. for each library card, we store the person's first and last names and their address. for each employee, we store their employee id, current salary, first and last name and their address. we also store the employee id of their current manager. each time we check out a book to a patron we need to store the date of the transaction, the employee who checked out the book to the patron, and the library card of the patron. some employees have library cards. if an employee patron turns in a book late, the fine that they pay is a percentage of their salary. some employees are authors who have library cards—they are allowed to check out as many books as they like.

Lusk corporation produces and sells 14,300 units of product x each month. the selling price of product x is $25 per unit, and variable expenses are $19 per unit. a study has been made concerning whether product x should be discontinued. the study shows that $72,000 of the $102,000 in monthly fixed expenses charged to product x would not be avoidable even if the product was discontinued. if product x is discontinued, the annual financial advantage (disadvantage) for the company of eliminating this product should be:

Which of the following is one of the five fundamental questions? which products will be in scarce supply and which in excess supply? who should appoint the head of the central bank? how much should society save? correct what goods and services will be produced?