Waterway Company purchased machinery on January 1, 2017, for $81,600. The machinery is estimated to have a salvage value of $8,160 after a useful life of 8 years.

(a) Compute 2017 depreciation expense using the sum-of-the-years'-digits method.

(b) Compute 2017 depreciation expense using the sum-of-the-years'-digits method, assuming the machinery was purchased on April 1, 2017.

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