Bridgeport Company is in the process of adjusting and correcting its books at the end of 2020. In reviewing its records, the following information is compiled. 1. Bridgeport has failed to accrue sales commissions payable at the end of each of the last 2 years, as follows. December 31, 2019 $3,400 December 31, 2020 $2,700 2. In reviewing the December 31, 2020, inventory, Bridgeport discovered errors in its inventory-taking procedures that have caused inventories for the last 3 years to be incorrect, as follows. December 31, 2018 Understated $16,300 December 31, 2019 Understated $19,000 December 31, 2020 Overstated $7,200 Bridgeport has already made an entry that established the incorrect December 31, 2020, inventory amount. 3. 4. At December 31, 2020, Bridgeport decided to change the depreciation method on its office equipment from double- declining-balance to straight-line. The equipment had an original cost of $109,200 when purchased on January 1, 2018. It has a 10-year useful life and no salvage value. Depreciation expense recorded prior to 2020 under the double-declining-balance method was $32,600. Bridgeport has already recorded 2020 depreciation expense of $14,000 using the double-declining- balance method. Before 2020, Bridgeport accounted for its income from long-term construction contracts on the completed-contract basis. Early in 2020, Bridgeport changed to the percentage-of-completion basis for accounting purposes. It continues to use the completed-contract method for tax purposes. Income for 2020 has been recorded using the percentage-of-completion method. The following information is available.