Confused on how to find the salvage value so I can calculate book value correctly

Assume you purchased a crane for $900,000 ten years ago. Accumulated depreciation has a balance of $460,000 and you sell the crane for $480,000. What is the book value of the crane? $ 440000 Was there a gain or loss on the sale? gain (enter either the word gain or the word loss) How much was the gain/loss? $ 20000 (enter only the number do not specify +/-)