S. 80IB : Industrial undertakings-Eligible business-No adjustment could be made in respect of expenses relating to other undertaking while computing deduction-Mineral oil, for purpose of claiming deduction under section 80-IB(9) includes natural gas and condensate and therefore profit derived from sale of natural gas and condensate was to be allowed as deduction under section 80IB(9). [S.80IA(5),80IB(9)]