Technological advancements that increase labor's productivity shift the labor supply curve to the right

A firm's short-run average cost is defined as

a. the ratio of total output to short-run total cost. b. the ratio of short-run total cost to total output. c. the additional cost of producing one more unit of output while some input is fixed. d. the additional cost of producing one more unit of output while all inputs are fixed.

Which of the following is a reason why the growth rates of high-income countries can be lower than that of low-income countries?

a. In high-income countries, the invention of new technology is difficult, expensive, and time consuming. b. In high-income countries, the invention of new technology is subject to diminishing marginal returns. c. In high-income countries, the marginal cost of production increases as output increases. d. In high-income countries, the average cost of production increases as output increases.