The forces that determine the cost of production are largely independent of the forces that shape demand

Is it more efficient for a group of musicians to perform a show "unplugged" (with acoustic instruments) or with state-of-the-art electric instruments?

A) Unplugged is more efficient because the instruments are considerably less expensive to operate. B) It depends on what the musicians are trying to accomplish. C) The use of electric instruments is more efficient because acoustic instruments have become more expensive in recent years. D) It depends exclusively on the relative ratios of energy output to energy input in each instrument class.

Monitoring

a. Gives the principle a better performance evaluation metric b. Allows the principle to better align the incentives of the agent with the goals of the principle c. Can be costly for the principal d. All of the above