Did the Tax Court lack jurisdiction due to improper notice of deficiency and fail to appropriately apply the Cohen rule for estimating business expenses?

QUESTIONS PRESENTED 1. Whether the Court erred in not dismissing the case for lack of jurisdiction on the ground that no notice of deficiency was issued to petitioner within 90 days of the date of the tax court , petition, and no notice of determination was issued to petitioner within 30 days of the date : of the tax court petition that would permit | petitioner to invoke the Tax Court’s jurisdiction, as mandated by 26 U.S.C. § 6213(a), invalidating the notice of deficiency for tax years 2015 and 2016 and affecting the Court’s jurisdiction. , 2. Whether the court failed to apply the Cohen rule appropriately concerning the estimation of business expenses when exact substantiation is unavailable, thereby ii potentially misinterpreting the statutory mandate for Tax Court decision reviews as outlined in 26 U.S.C. § 7482(a) and deviating from established legal precedent that recognizes the practical limitations on petitioner’s record-keeping.