A corporation owns land on which there are both an active coal mine and timber. The corporation also owns an office building and the land on which it is located. The corporation uses three plant asset accounts: (1) Land and Buildings (depreciation calculated using the straight-line method). (2) Timber (depreciation calculated using the declining-balance method). (3) Coal Mine (depreciation calculated using the declining-balance method). Do you agree with the accounting procedures being used? Explain your answers.