Use the 2012 marginal tax rates to compute the tax owed by the following person an unmarried head at household with two dependent children. Click the icon to view the 2012 marginal tax rates. The income tax owed is exist. (Round to the nearest dollar as needed.) Use the 2012 marginal tax rates to compute the tax owed by the following person an unmarried head at household with two dependent children. Click the icon to view the 2012 marginal tax rates. The income tax owed is exist. (Round to the nearest dollar as needed.)