Determination of determinable questions: binding tax rulings and deemed determinations protect taxpayer reliance when procedures are followed. Applications may be made to the Commissioner for determination of specified determinable questions about VAT treatment of transactions, covering dealer status, registration, taxable quantum, classification, taxability, valuation, tax credit entitlement, composition scheme applicability, and tax period. Applications are barred once an audit notice is served or an assessment for the relevant period is issued. The Commissioner must determine within the prescribed period; failure to do so plus the applicant's implementation in reliance and a stated proposed determination results in a deemed determination in the applicant's terms. Determinations can be limited or qualified and protect the applicant from inconsistent assessments and penalties for relied-upon transactions.