; and (ii) a detailed statement with respect to each participating 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 participating Federal agency. (C) Response A participating 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 a proposed agency action will require action by more than one Federal agency and the lead agency has determined that it requires preparation of an environmental document, the lead and cooperating agencies shall evaluate the proposal in a single 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 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 document shall include a statement of purpose and need that briefly summarizes the underlying purpose and need for the proposed agency action. (e) Page limits (1) Environmental impact statements (A) In general Except as provided in subparagraph (B), an environmental impact statement shall not exceed 150 pages, not including any citations or appendices. (B) Extraordinary complexity An environmental impact statement for a proposed agency action of extraordinary complexity shall not exceed 300 pages, not including any citations or appendices. (2) Environmental assessments An environmental assessment shall not exceed 75 pages, not including any citations or appendices. (f) Sponsor preparation A