Given the following information for a firm, how much did the firm sell its patent $($a long$-$term intangible asset$)$ for?

From the $2023$ income statement:

Gain on sale of patent $=$$$300$

Amortization expense on patent $=$$$800$

From the $2023$ balance sheet:

Patents decreased by $$2,000$

$$3,100$

$$1,000$

$$1,500$

$$2,500$