A firm first hires 50 workers, each of whom works 40 hours per week, and its total output is 18 000 units. It later hires 10 more workers, again each working 40 hours, and total output increases to 19 200 units. What effect does this increase in employment have on labour productivity?
- Adecreases it by 1 unit
- Bdecreases it by 40 units
- Cincreases it by 120 units
- Dincreases it by 1200 units