1.Determine the amount of gain that Taxpayers (a married couple filing a joint return) must include in gross income in the following situations: (a)Taxpayers sold their principal residence for $600,000. They had purchased the residence several years ago for $200,000 and lived in it over those years. (b)Taxpayers in (a), above, purchased another principal residence for $600,000 and sold it 2 years later for $1 million. (c) What result in (b), above, if the second sale occurred 1 years later? (d)What result in (b), above, if Taxpayers had sold their first residence and were granted nonrecognition under former Section 1034 (the rollover provision) and, as a result, their basis in the second residence was $200,000? (e) What result in (a), above, if the residence was Taxpayers' summer home which they used 3 months of the year? (f)What result if Taxpayer who met the ownership and use requirements is a single taxpayer who sold a principal residence for $400,000 and it had an adjusted basis of $190,000 after Taxpayer validly took $10,000 of post-1997 depreciation deductions on the residence which served as an office in Taxpayer's home?