Silver Construction Inc. purchased two excavators on January 1, 2021. The first excavators cost is $800,000 and has an estimated useful life of 10 years, is expected to be used 100,000 hours annually and its salvage value is 17,000 at the end of its useful life. The second excavators cost is $900,000 and has an estimated useful life of 11 years, is expected to be used 100,000 hours annually and its salvage value is 22000 at the end of its useful life. Compute the amount of depreciation expense of the second excavator for the year ended December 31, 2021, using the units of activity method of depreciation.

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