Answer:
a. decreased by 4%
Explanation:
In 2011 modern electronics produce 60,000 calculators, employing 80 workers, each of whom worked 8 hours per day. In 2012, the same firm produce 76,500 calculators, employing 85 workers, each of whom worked 10 hours per day. Productivity at Modern Electronic increased by
In 2011 - 60,000 / (80 x 8) = 93.75 units per hour
In 2012 - 76,500 / (85 x 10) = 90 units per hour
(93.75 - 90) / 93.75 = 4% decrease