On January 10,2000 , LND Co. purchased for $950,000 a building that had an estimated residual value of $500,000 and a useful life of 40 years. On January 13,2020 , a $375,000 addition to the building increased its residual value by $40,000. Calculate straight-line amortization expense for 2020 . Before we can calculate the straight-line amortization expense for 2020, we must first calculate the new book value. Now, we can calculate the revised straight-line amortization expense for 2020. Select the formula, enter the amounts, and calculate the company's 2020 amortization on the building. (Abbreviations used: amort. = amortization.)