Now take into account that TFP growth was in fact positive in both countries during this period and approximately equal to 2%. How does your answer to question (i) change under this scenario? How does the long run growth rate of production per capita in both countries depend on the rate of TFP growth?

What does your answer in (iv) tell you about the importance of productivity growth for long run improvements in standards of living? Why can't we count on continuously increasing our capital-labor ratio to grow in the long run?