Codelco, a state-owned Chilean group, is the world’s single biggest copper producer, producing about 1.76 million metric tons of copper a year. BHP Billiton, the Australian group, produces about 1.14 million metric tons of copper a year. The marginal cost of producing another metric ton of copper is around $9000. In making the calculation, the cost of labor, materials, and other inputs that increase when more copper is produced are taken into account. The CEO of BHP Billiton decides to take a bank loan to improve its revenues, but the Board says: “If we take into account the amount we pay on this loan, it adds $1000 per metric ton of copper to our marginal cost of production.” Do you agree with this aspect? Briefly explain.