Savvy Sisters, a high-end furniture production company, has purchased a new plant and has asked you: Over what period should our new plant be depreciated? The plant's estimated useful life is 40 years. Using a guidance sandwich, respond to this question. (That is, introduce the issue, quote relevant guidance, then summarize how the guidance applies to the issue.) Do not just answer from your general knowledge. This is an issue that must be researched and supported by the Codification.