If the total cost incurred in hiring ten workers by a firm is $45, and the total cost incurred when the eleventh worker is hired is $60, the marginal cost of hiring the eleventh worker is:

A key component of the Keynesian model is that

A) people are not fooled by money illusion. B) prices are flexible. C) prices are sticky. D) wages are flexible.

The demand for money curve is drawn

A) holding several things constant, including the price level and interest rates. B) with interest rates on the vertical axis and the curve sloping down since lower interest rates mean the "price" of holding money has fallen. C) holding several things constant, including GDP and interest rates. D) with interest rates on the horizontal axis, and the curve sloping up since the "price" of holding money varies directly with the interest rate.