The following formula is used to calculate the specific gravity of a material. Where SG = specific gravity, Ï = density of the material (kg/m3), ÏW = density of water ( kg/m3). The reference density of water at 4oC (39oF) is used as the reference as these are the conditions of maximum density.
Most business owners donât know how long they should hold on to old records. According to the IRS, hereâs how long you should keep those records: Permanently: 1  general ledgers and journals. 2  payroll records, including W-2s, 940s, 941s. 3  year-end financial statements.4  tax returns and supporting documents. 5  articles of incorporation, bylaws, meeting minutes, etc. 6  retirement plan records.ost business owners donât know how long they should hold on to old records. According to the IRS, hereâs how long you should keep those records: Permanently: 1  general ledgers and journals. 2  payroll records, including W-2s, 940s, 941s. 3  year-end financial statements. 4  tax returns and supporting documents.
Department of Taxation and Finance. Recordkeeping. You must keep records that allow you to prepare complete and accurate tax returns for your business. You must also keep documents, such as canceled checks, receipts, cash register tapes, purchase orders, and other sales records to support your business records. Generally, you must keep records and supporting documents for at least three years after you file a return. Your records may be in paper, electronic format, or both. You must be able to compare records from one time period (such as month, quarter, or year) with records from another period.