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Onslow Co. purchases a used machine for $144,000 cash on January 2 and readies it for use the next day at a $6,000 cost. On January 3, it is installed on a required operating platform costing $1,200, and it is further readied for operations. The company predicts the machine will be used for six years and have a $17,280 salvage value. Depreciation is to be charged on a straight-line basis. On December 31, at the end of its fifth year in operations, it is disposed of