Marie is buying bananas. she decides that she would like to purchase three bananas at the price of $0.25 per banana, but not a fourth banana. which of the five foundations of economics, illustrated above, best describes marie's thinking? choose one: a. opportunity cost b. trade-offs c. marginal thinking d. trade creates value e. incentives

10. which of the following is true regarding preretirement inflation? a. defined-benefit plans provide more inflation protection than defined-contribution plans. b. because of preretirement inflation, possible investment-related growth is increased for defined-contribution plans. c. all types of benefits are designed to cope with preretirement inflation. d. preretirement inflation is generally reflected in the increase in an employee's compensation level over a working career.

When used-car dealers signal the quality of a used car with a warranty, a. buyers believe the signal because the cost of a false signal is high b. it is not rational to believe the signal because some used-car dealers are crooked c. the demand for lemons is eliminated d. the price of a lemon rises above the price of a good used car because warranty costs on lemons are greater than warranty costs on good used cars

The state in which the manufacturing company you work for is located regulates the presence of a particular substance in the environment to concentrations ≤ x. recently-released, reliable research endorsed by the responsible federal agency conclusively demonstrates that the substance poses no risks at concentrations up to 5x. your company has asked you to consider designing a new process with a waste discharge stream containing up to 2x of the substance. based on the stated conditions, describe this possible.