(I) Where for any rea,on the whole or any pa1 t of the turnover of busmess of a dealer has escaped assessment to tax in any year or has been under-assessed or has been asse 'sed at a rate lower than the rate at wh1ch 1t is assessable, or any dedu ction has been wrongly made therefrom, the assessing autho11ty may, at any time w1thin four years from the exp1ry of the year to wh1ch the tax relates, proceed to determine to the best of its judgment the turnover which has escaped assessment to tax or has been under-assessed or has been a~sessed at a rate lower than the rate at which it 1s assessable or the deductiOn that has been wrongly made and assess the tax payable on such turnover after issuing a notice on the dealer and after makmg such enqmry as 1t may consider necessary :
Provided that before makmg an assessment under this sub-section the dealer shall be given a 1easonab1e opportunity of being heard.
(2) In makmg an assessment under sub-sectwn (I), the assessing authority may, 1f it 1s satisfied that the escape from assessment 1' due to wJiful non-d1sclo5ure of assessable turnover by the dealer, direct the dealer to pay, in additwn to the tax assessed under sub-sect10n (I), a penalty not exceedmg one and a half t1mes the tax so assessed :
Provided that no penalty under tl11S sub-section shall be Imposed unless the deale1 affected has had a reasonable opportumty of showing cause against such Impos1t10n.
(3) The powers under sub-sectiOn (I) may be exerc1sed bv the assessmg auth011ty even though the 01 igmal 01 der of assessment, 1f any, passed m tile matter, has been the subject matter of an appeal or revision.
(4) In computmg the penod of limllatlon for the purposes of this sectwn, the time durmg wh1ch the proceedmgs for assessment remained stayed under the mders. of a civJ! court or other competent authority shall be excluded.