Most economists analyze economic issues from a normative approach

When economists state that the opportunity cost of a product increases as more of it is produced, what do they mean? For instance, what is the opportunity cost? And, where in a PPF diagram does this statement apply and where does it not apply?

What will be an ideal response?

Gradual adjustment of prices and wages to an increase in the aggregate demand curve implies that the aggregate supply curve is:

a. horizontal. b. vertical. c. upward sloping but not vertical. d. downward sloping.