could you solve this question?

Question :2 Best Care is a nursery school for pre-kindergarten children. The school has determined that the following biweekly revenues and costs occur at different levels of enrolment: Number of Students Enrolled Total Revenue Total Costs 10 $3,000 $2,100 15 4,500 2,700 16 4,800 2,800 20 6,000 3,200 21 6,300 3,255 Required: Compute the following: A. marginal cost when the twenty-first student enrols in the school. B. average cost per student when 16 students enroll in the school