Elvin, a single taxpayer 45 years of age, sells his residence in 2017. He receives $35,000 in cash, and the buyer assumes his $100,000 mortgage. Elvin also pays $8,100 in commissions and transfer costs.

a. Calculate the amount realized on the sale. $ __________

b. If the residence was acquired in 1987, and its adjusted basis is $75,000, calculate the amount and nature of the taxable gain on the sale (assuming he does not purchase a new residence)._______________