Presented below are selected transactions at Metlock, Inc. for 2020. Jan. 1 Retired a piece of machinery that was purchased on January 1, 2010. The machine cost $61,800 on that date. It had a useful life of 10 years with no salvage value. June 30 Sold a computer that was purchased on January 1, 2017. The computer cost $39,000. It had a useful life of 5 years with no salvage value. The computer was sold for $15,800. Dec. 31 Discarded a delivery truck that was purchased on January 1, 2016. The truck cost $36,540. It was depreciated based on a 6-year useful life with a $3,000 salvage value. Journalize all entries required on the above dates, including entries to update depreciation, where applicable, on assets disposed of. Metlock, Inc. uses straight-line depreciation. (Assume depreciation is up to date as of December 31, 2019.) (Credit account titles are automatically indented when amount is entered. Do not indent manually. Record journal entries in the order presented in the problem. If no entry is required, select "No Entry" for the account titles and enter O for the amounts. Do not round intermediate calculations.) Date Account Titles and Explanation Debit Credit (To record depreciation to date of disposal) Jan. 1 June 30 Dec. 31 June 30 T Jan. 1 June 30 Dec. 31 Dec. 31 (To record depreciation to date of disposal) (To record retirement of truck)