Help! Im filling out a 1040 for a retired couple (both elderly) for an accounting project. A standard deduction applies. Two items will receive a 0% tax rate (long term capital gain and a qualified dividend) and the rest will receive a 12% tax rate. When you deduct the standard deduction from the AGI, how do you then figure out taxes if the items have varying tax rates? Please explain your answer as I am so confused, thank you!