What is the recognized gain or loss from the sale of July 1?

In her will, Maria Chavez (see item 10) left Sofia a vacant lot on Wright Street. Maria had paid $15,000 for the property, and it had a value of $19,000 when she died. Maria had purchased the lot because it was adjacent to Northern Michigan University property and she expected the school to eventually expand the campus. By 2021, it has become clear that the university did not have the funds to expand the campus. Consequently, on July 1, 2021, Sofia sold the lot for $22,200. The buyer pays the real estate taxes of $800 for 2021. Sofia received a Form 1099-B as documentation for this transaction which did not report the basis of this property.