Can I get it step by step on how to solve it please

Q Search Case 3: Overstated depreciation for ong-term assets In 2009 Lufthansa, the German national airline, reported that it depreciated its aircraft over 12 years on a straight- line basis, with an estimated residual value of 15 percent of initial cost. Air France-KLM, an airline formed in 2004 by the merger of the French airline Air France and the Dutch airline KLM, is one of Lufthansa's main competitors. In contrast to Lufthansa, Air France-KLM reported that its aircraft depreciation was also estimated using the straight- line method but assuming an average life of 20 years and no residual value. Case 3: Overstated depreciation for long-term assets Lufthansa reported in its 2009 Annual Report the total cost of its aircraft at the beginning of 2009 as 17,918 million and that accumulated depreciation was 10,547 million. - What if Lufthansa used the same useful life and salvage estimates as Air France-KLM? What would be the effect on 2009 financial statements (assuming that they maintain their method for tax purposes, tax rate=25%)