In Class B, Class C, or Class D airspace or within the lateral boundaries of the surface area of Class E airspace designated for an airport, the operator obtains prior authorization from the Administrator or designee before operating and complies with all airspace restrictions and prohibitions. (6) In Class G airspace, the aircraft is flown from the surface to not more than 400 feet above ground level and complies with all airspace restrictions and prohibitions. (7) The operator has passed an aeronautical knowledge and safety test described in subsection (g) and maintains proof of test passage to be made available to the Administrator or law enforcement upon request. (8) The aircraft is registered and marked in accordance with chapter 441 of this title and proof of registration is made available to the Administrator or a designee of the Administrator or law enforcement upon request. (b) Other operations Unmanned aircraft operations that do not conform to the limitations in subsection (a) must comply with all statutes and regulations generally applicable to unmanned aircraft and unmanned aircraft systems. (c) Operations at fixed sites (1) Operating procedure required Persons operating unmanned aircraft under subsection (a) from a fixed site within Class B, Class C, or Class D airspace or within the lateral boundaries of the surface area of Class E airspace designated for an airport, or a community-based organization conducting a sanctioned event within such airspace, shall make the location of the fixed site known to the Administrator and shall establish a mutually agreed upon operating procedure with the air traffic control facility. (2) Unmanned aircraft weighing more than 55 pounds A person may operate an unmanned aircraft weighing more than 55 pounds, including the weight of anything attached to or carried by the aircraft, under subsection (a) if— (A) the unmanned aircraft complies with standards and limitations developed by a community-based organization and approved by the Administrator