Ms. Smith purchased land 40 years ago that was situated next to a local river. She paid $10,000 for the land. Due to recent commercial development, the riverside plot of land is now worth $100,000. Ms. Smith decides to sell the land for its present value using the installment sale method. If she contracts with a buyer to receive $20,000 a year for five years, how much of each annual payment will be considered a return of basis in the property and not taxable as capital gain