On January 1, 2019, SBA Inc. purchased a machine for $185,000. The machine's estimated life is six years, and its salvage value is $35,000. This machine has a production capacity of 12,000 units allocated as follows: 2019: 1900 units | 2020: 2400 units | 2021: 2200 units | 2022 3100 units | 2023: 1300 | 2024: 1100 What's the amount of the Book-value beginning 2023 using the units-of-production method