The tax payable under the Act shall be calculated on the basis of-
(a) The sale price of the goods at such rate not exceeding fifty percent; or
(b) The weight or volume of the goods at such rate not exceeding fifty rupees per litre; or
(c) Any combination of clause (a) or (b)
as the State Government may, by notification, specify and subject to such conditions and restrictions as may be specified in the said notification.