Gladys, what John the Turbotax person said in his reply above is that TurboTax knows your Total income you entered, but it doesn't know how much of that income came between January - March 26th and which part of the income is from March 27th to December 31st. Only you can know that. So figure out how much of your full year tax was from March 27th to December 31st and enter it in line 18.
John's explanation was actually very good
