to energy costs, as determined by the Secretary. (B) List of energy-intensive manufactured goods (i) Initial list Not later than 180 days after the date of the enactment of this Act, the Secretary shall publish a list of goods which qualify as energy-intensive manufactured goods. (ii) Updates Not less frequently than annually, the Secretary shall update the list published under this subparagraph. (5) Greenhouse gas The term greenhouse gas has the meaning given such term under section 211(o)(1)(G) of the Clean Air Act, as in effect on the date of the enactment of the American Opportunity Carbon Fee Act of 2019 . (6) Natural gas The term natural gas has the same meaning given such term under section 613A(e)(2). (7) Petroleum product The term petroleum product has the same meaning given such product under section 4612(a)(3). (8) Supply chain The term supply chain means extraction and processing of coal and natural gas, extraction and refining of petroleum products, and the transmission, transport, storage, distribution, import, export, and other activities related to supplying coal, petroleum products, and natural gas to a consumer, not otherwise covered elsewhere in this subchapter as determined by the Administrator of the Environmental Protection Agency. (9) Ton (A) In general The term ton means 1,000 kilograms. In the case of any greenhouse gas which is a gas, the term ton means the amount of such gas in cubic meters which is the equivalent of 1,000 kilograms on a molecular weight basis. (B) Fractional part of ton In the case of a fraction of a ton, any fee imposed by this subchapter on such fraction shall be the same fraction of the amount of such fee imposed on a whole ton. (10) United States The term United States has the meaning given such term by section 4612(a)(4). (b) Other rules (1) Assessment and collection Payment of the fee imposed by sections 4691, 4692, and 4693 shall be assessed and collected in the same manner as taxes under this subtitle. (2) Regulations The Secretary shall prescribe such