Economics · Macroeconomics

Consider the following statements about Marginal Efficiency of Capital (MEC): I. MEC is defined as the rate of discount which equates the present value of expected returns from a capital asset to its supply price. II. The MEC curve depicts a positive relationship between MEC and the stock of capital. III. The investment decision rule is: invest if market rate of interest (i) is less than MEC (r). IV. MEC is also known as Natural Interest Rate, Net Capital Productivity, and Internal Rate of Return. Which of the above statements are CORRECT?