(a)at the rates specified in Part I of ] [Schedule I ] [ Substituted by Act 66 of 1976, Section 27, for " the Schedule" (w.e.f. 1.4.1977).][* * *] [ Omitted by Act 32 of 1971, Section 34 (w.e.f. 1.4.1972).][or [Substituted by Act 19 of 1970, Section 26, for sub-Section (4)(w.e.f. 1.4.1971). ]