-The Table Shows Information for Jen's Gymnastics

-The table shows information for Jen's Gymnastics.Jen hires coaches and can charge $20 per hour for gymnastics lessons.The value of marginal product for the second coach is ________ because ________.

A) 13; 2 coaches can train 13 gymnasts
B) 6; the second coach can train an extra 6 gymnasts
C) $120; the second coach's marginal product is 6 gymnasts and lessons cost $20
D) $260; the first two coaches can earn $20 for each of the 13 gymnasts
E) $40; each coach can charge $20 per student