What is the fundamental principle that economists use when evaluating the costs and benefits of production?
A) cost of goods principle B) production principle
C) marginal principle D) supply and demand principle
Question 2
In the income-expenditure model, equilibrium output is the level of output at which the 45-degree line intersects the planned expenditures line. Explain why this output level is an equilibrium level.
Illustrate your answer with a diagram of the income-expenditure model.