For each of the following statements, decide whether it is true or false, and explain your answer in at most two sentences using the material you learned in the course. No points will be given without an appropriate explanation! Question 1.1 We have used the Cobb-Douglas production function because that is the only production function with constant returns to scale. Question 1.2 The capital share and the labor share cannot be constant if there is a third factor of production, like costly entrepreneurial work. Question 1.3 Increasing returns to scale imply that the marginal product of capital is constant or increasing in K. Question 1.4 The failure of our production model to explain differences in income per capita across countries is largely due to the incorrect assumption of perfect competition. Question 1.5 If we assume that TFP is identical across countries, then our model of production will dramatically underpredict cross-country differences in output per capita.