MOHAN, J.

Since all these writ petitions raise one and the same question of law, they are dealt with under a common judgment. It is enough to note the facts in Writ Petition No. 869 of 1982.

2. The petitioners are a company incorporated under the Indian Companies Act of 1913. The incorporation took place on 12th July, 1964. Its registered office is at No. 109, Nungambakkam High Road, Madras 600 034. The petitioners are manufacturers of sugar and other by-products at their factory situate at Vadapathimangalam, Thanjavur district. They are assessed to sales tax. They are assessees on the files of the Deputy Commercial Tax Officer, Mannargudi, Thanjavur district (first respondent herein).

3. The sugarcane is a raw material for manufacture of sugar. It is subject to purchase tax under section 7-A read with Sl. No. 62 of the First Schedule to the Tamil Nadu General Sales Tax Act, 1959. The point of levy is "at the point of last purchase in the State". Presently, the rate of tax is 12 per cent. An additional sales tax is also levied in addition to the above, at 0.7 per cent. on the taxable turnover under the Tamil Nadu Additional Sales Tax Act, 1970.

4. The petitioners submit mon