(1) Subject to provisions of sub-section (2), the amount of tax due from a registered dealer or a dealer liable to be registered under this Act shall be assessed in the manner hereinafter provided, for each tax period or periods during which the dealer is so liable.

(2) If a registered dealer furnishes the return in respect of any tax period within the prescribed time and the return so furnished is found to be in order, it shall be accepted as self-assessed subject to adjustment of any arithmetical error apparent on the face of the said return.