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.
I would advise you to keep records and tax returns for the years that include out-of-the-ordinary transactions (sales or donations of property), and income from activities such as stock option exercises, trust income, etc., for six years after the filing date of the return.MoneyWatch) Most people hold on to their statements for financial, credit and utility accounts a few years, and when the pile gets too big, it's time for the shredder. 1  12 things to keep in a safe at home, not at a bank. 2  Keeping a safe deposit box safe. 3  How long to keep bank records.