The amount of human capital per worker grows by 6% a year in a country. Estimates of the aggregate production function for the country show that holding physical capital per worker and technology constant, for each 1% increase in human capital per worker, output per worker increases by 0.5%. The growth in human capital per worker in the country accounts for approximately _____% of productivity growth per year. Please choose the correct answer from the following choices, and then select the submit answer button. Answer choices 0.5 3 6 30