6. Harrison, Carla and Fred are housepainters. Harrison and Carla can paint 100 square metres per hour using a standard paintbrush, and Fred can paint 80 square metres per hour. Any of the three can paint 200 square metres per hour using a roller. LO 13.6 MEDIUM a)Assume Harrison, Carla and Fred have only paintbrushes at their disposal. What is the average labour productivity, in terms of square metre per painter-hour, for the three painters taken as a team? Assume that the three painters always work the same number of hours. b)Repeat part (a) for the cases in which the team has one, two, three or four rollers available. Are there diminishing returns to capital?

c)An improvement in paint quality increases the area that can be covered per hour (by either brushes or rollers) by 20 per cent. How does this technological improvement affect your answers to part (b)? Are there diminishing returns to capital? Does the technological improvement increase or reduce the economic value of an additional roller?