Efficiency in a market is achieved when:. a. a social planner intervenes and sets the quantity of output after evaluating buyers' willingness to pay and sellers' costs.
b. the sum of producer surplus and consumer surplus is maximized.
c. all firms are producing the good at the same low cost per unit.
d. no buyer is willing to pay more than the equilibrium price for any unit of the good.

Retirement investment advisors, inc., has just offered you an annual interest rate of 4.4 percent until you retire in 40 years. you believe that interest rates will increase over the next year and you would be offered 5 percent per year one year from today. if you plan to deposit $13,000 into the account either this year or next year, how much more will you have when you retire if you wait one year to make your deposit?

Asmall town wants to build some new recreational facilities. the proposed facilities include a swimming pool, recreation center, basketball court and baseball field. the town council wants to provide the facilities which will be used by the most people, but they face budget and land limitations. the town has $400,000 and 14 acres of land. the pool requires locker facilities which would be in the recreation center, so if the swimming pool is built the recreation center must also be built. also, the council has only enough flat land to build the basketball court or the baseball field. the daily usage and cost of the facilities (in $1,000) are shown below. which facilities should they build? facilityusagecost ($1,000)landswimming pool4001002recreation center5002003basketball court3001504baseball field2001005

Opportunity cost is calculated by which of the following? a. adding the value of all lost opportunities. b. subtracting all costs from the total benefit. c. calculating the cost of time, energy, and sacrifice. d. finding the value of the best option that is not chosen.