Determination of tax clarifies stays, hearing rights, limits on demands, modification effects, interest and recovery procedures. Determination of tax provisions exclude periods of judicial stay from limitation computations, require the proper officer to limit assessments where fraud or wilful misstatement is not established, mandate reasoned orders and adherence to notice grounds and amounts, provide personal hearing rights and limited adjournments, adjust interest and penalty when tax is modified on appeal, require interest on short paid tax whether or not specified in the order, allow exclusion of periods while higher appeals on legal issues are pending, and provide for recovery of unpaid self assessed tax under the recovery provisions.