Equipment was purchased at the beginning of 2013 for $100,000 with an estimated product life of 300,000 units. The estimated salvage value was $4,000. During 2013, 2014, and 2015, the equipment produced 80,000 units, 120,000 units, and 40,000 units, respectively. The machine was damaged at the beginning of 2016, and the equipment was scrapped with no salvage value.

1. Determine depreciation using the productive-output method for 2013, 2014, and 2015.

2. Give the entry to write off the equipment at the beginning of 2016.