; and (ii) a detailed statement with respect to each involved Federal agency and each factor listed in paragraph (1) regarding which agency should serve as lead agency. (B) Transmission The Council shall transmit a request received under subparagraph (A) to each involved Federal agency. (C) Response An involved Federal agency may, not later than 20 days after the date of the submission of a request under subparagraph (A), submit to the Council a response to such request. (D) Designation Not later than 40 days after the date of the submission of a request under subparagraph (A), the Council shall designate the lead agency with respect to the relevant proposed agency action. (b) One document To the extent practicable, if there are 2 or more involved Federal agencies with respect to a proposed agency action and the lead agency has determined that section 102(2)(C) requires the issuance of an environmental document, such requirement shall be deemed satisfied with respect to all involved Federal agencies if the lead agency issues such an environmental document. (c) Request for public comment Each notice of intent to prepare an environmental impact statement under section 102 shall include a request for public comment on potential alternatives or impacts and on relevant information, studies, or analyses with respect to the proposed agency action. (d) Statement of purpose and need Each environmental impact statement shall include a statement of purpose and need that briefly summarizes the underlying purpose and need for the proposed agency action. (e) Estimated total cost The cover sheet for each environmental impact statement shall include a statement of the estimated total cost of preparing such environmental impact statement, including the costs of agency full-time equivalent personnel hours, contractor costs, and other direct costs. (f) Sponsor preparation A lead agency may allow a project sponsor to prepare an environmental assessment or an environmental impact statement, if such agency provides such sponsor with