Single Taxpayer buys a mountain cabin on January 1, 2013 for $200,000 Which Single used as a vacation home through December 31, 2015. In 2015, Single sells her principal residence at a gain which is excluded under $ 121. On January 1, 2016, Single moves into the mountain cabin and uses it as her principal residence. (a) If Single sells the mountain cabin for $350,000 on January 1, 2018, how much of the gain is included in her gross income? (b) What result in (a), above, if Single sells the mountain cabin for $900,000? (c) What result in (a), above, if Single purchased the mountain cabin and began using it as a vacation home on January 1, 2004? (d) Do the nonqualified use rules apply to Single if Single purchases and uses a principal residence for two years, then rents it out for two years prior to selling it? for 10