Final answer:
To calculate the gain or loss, subtract the accumulated depreciation from the initial cost to find the net book value. Compare the net book value to the amount received from the sale to determine the gain or loss. Therefore the correct answer is $5,000.
Step-by-step explanation:
To calculate the gain or loss on the transaction, we need to find the net book value and compare it to the amount received from the sale. The net book value is calculated by subtracting the accumulated depreciation from the initial cost of the equipment. In this case, the net book value is $310,000 - $260,000 = $50,000. Since the equipment was sold for $55,000, there is a gain of $55,000 - $50,000 = $5,000.