Arnold gave land to his son, Bruce. Arrold's $L$ asis in thie land was $$125,000$ and its fair market value at the date of the gift was $$175,900.$ Bruce boriowed $$140,000$ from a bank to improve the property. He sold the property to Deila for $.$ Della paid Bruce $$90,000$ in cash, assumed his $$120,000$ mortgage, and agrecis to pay $$170,000$ in two years. Bruce's selling expenses were $$10,000.$

What is Bruce's installment sale gain in the yeai of sale? Ple se show your calculations.