An asset was purchased for $150,000. It had an estimated salvage value of $30,000 and an estimated useful life of 10 years. After 5 years of use, the estimated salvage value is revised to $24,000 but the estimated useful life is unchanged. Assuming straight-line depreciation, depreciation expense in year 6 would be $18,000 $13,200. $9,000. $12,600