A company would like to register the annual depreciation expenses of a generator that was acquired for $250,000 with an expected useful life of 4 years. Using 150%-declining-balance method: a) What is the expected book value of the generator at the end of 1st and 4th year? b) What is the depreciation amount in the 2nd and 4th years? c) When does the company need to switch to a straight-line model to have a book value equal to a market value of $15,000 at the end of the useful life (fill the table below to support your answer)? (Show detailed calculations)