S. 4 : Charge of income-tax-Sales tax exemption from State Government-Subsidy held to be capital receipt, and High Court order on that issue affirmed-Income accrual-Duty drawback-Income does not accrue merely on export; Tribunal was justified in remanding matter for limited verification whether claim was accepted by authorities in relevant year-High Court erred in interfering with remand-Tribunal’s order restored.[S. 5, Art. 136]