Your new client Robert Duff is very interested in reducing his tax liability, and by his very nature he is somewhat aggressive. A friend recently told him that cash transactions are more difficult for the IRS to identify, and thus, tax. (His friend has been using this strategy for years and has never been audited.) He has had a very profitable year in 2023 and demands that you help him reduce his tax liability. Duff is contemplating using this "strategy" of not reporting a large portion of the cash collected in his business. He plans on reporting all credit card transactions which account for 70% of his sales. Cash sales account for 30% and he currently keeps all cash sales in a safe in his basement. Answer the following questions with respect to the Duff Assignment: What Internal Revenue Code Section (IRC) should you consider when responding to Duff's inquiries? Based upon your research, is Duff using tax planning? What kinds of risks are involved with Duff's strategy? (Consider risks for the taxpayer and taxpreparer)