write a 1000-word long part 1 of 3 parts of an article's body. the topic: marginal abatement cost curve (MACC) and sustainability in the oil and gas industry. you Must use intext citation and provide a ref. page using Chicago style for the intext and the ref. page. parts 1 and 2 should not have conclusions. the three parts should forma coherent body of this article. INTEXT citation is a must