On its 31/12/2020 Balance Sheet, Star company lists a Machine with cost of $ 70,000, and net book value of $49,375. If the equipment has a useful life of 8 years, and a salvage value of $10,000, and Star uses the SLM to calculate depreciation, when was the machine purchased? O a. On 1/7/2018 O b. All answers are wrong O c. On 1/4/2018 dd. On 1/1/2018