The maximum floor area ratio permitted on a zoning lot is 7.52 for residential use, 6.0 for commercial use and 7.5 for community facility use. In no event shall the total floor area ratio for all uses exceed 7.52. However, for developments or enlargements on qualifying transit improvement sites, a floor area bonus for mass transit station improvements may be granted by the City Planning Commission pursuant to the provisions of Section 66-51 (Additional Floor Area for Mass Transit Station Improvements). For the purposes of this paragraph, defined terms additionally include those in Section 66-11 (Definitions).