A description of the various residential areas proposed, indicating for each such area the general extent, size and composition in terms of the number of dwelling units, the percentage by housing type (single-family detached, duplex, townhouse, garden apartment, etc.) and a general description of the intended market (luxury, middle-income, moderate-income, elderly, family units, etc.), plus a calculation of the residential density in dwelling units per gross acre (total area, including interior roadways) for each such area.