A new computer lets a phlebotomist finish a blood draw in 10 minutes. The supplies for each draw cost $4, and the phlebotomist earns $20 per hour. The phlebotomy lab is designed to accommodate 20,000 draws per year. Its rent is $80,000 per year. Assuming the lab operates at full capacity, are the average and marginal cost of a blood draw?

If the rent for the lab rises to $100,000 per year, what are the average and marginal cost of a blood draw?

Explain your results.