Determination of tax: procedural limits on demands, guaranteed hearings, and adjusted interest and penalty after appellate modification. Section 75 prescribes that periods of judicial or appellate stay are excluded from limitation calculations; if fraud or wilful misstatement is not established on appeal, the proper officer must determine tax under ordinary notice provisions; adjudication orders must state facts and grounds, demands cannot exceed notice-specified grounds or amounts, interest is payable regardless of inclusion in the order, interest and penalty follow any appellate modification of tax, and adjudication is deemed concluded if the order is not issued within the statutory period.