12. The marginal cost for a company to produce q items is given by MC(q) = 0.005q ^2-0.7q+625. The company's fixed costs are $8300 The cost at a production level of 10 items is $ 13. The marginal cost for a company to produce q items is given by MC(q) = 0.004q^2-0.6q+615. The company's fixed costs are $8200 The marginal cost of producing 110 items is $ per item 14. The marginal cost for a company to produce q items is given by MC(q) = 0.002q^2-0.9q +625. The company's fixed costs are $8000. The cost to increase production from a production level of 340 items to a production level of 510 items is S