DEPRECIATION Question 1: Inverness Corporation purchased a new machine on January 1, 2013. The machine cost $210,000 and had an estimated salvage value of $30,000. Inverness estimated that the machine will have a useful life of 6 years or 140,000 units. Inverness uses the machine in its manufacturing operations and produces 80,000 units in Year 1; 10,000 units in Year 2; 20,000 units in Year 3; 15,000 in Year 4; 10,000 units in Year 5; and 5,000 units in Year 6. Double Declining balance.