18. Company "A" has a car. The cost of the car in 1/12/2018 is 30,000. Its estimated useful life is 6 years. The estimated salvage value is 2,500$. The productive life is 300,000 hours. Based on the information above, please solve question 18,19,20, and 21. 18- assume that the company used the car for 6,000 hours. Find the depreciation expense for 2018 using activity method: (2 Points) 660 550 o o o o 490 458