Suppose we have an asset with an initial cost of $10,000,$ a useful life of $5$ years and an estimated residual value of nil. The asset is now $3$ years old and therefore has a carrying value $($net book value$)$ of $4,000.$ After $3$ years, the assets value is reviewed and its fair value is $6,000.$ Show how the depreciation will be adjusted under the gross method and net method.