S. 154 : Rectification of mistake apparent from record-No merger of order passed under Section 143(3) r.w.s 144C(1) with the reassessment order passed under section 147 if issues forming subject matter of assessment order not part of reassessment order which is quashed and assessment order can be rectified by AO with respect to those issues-Rectification cannot be made after CIT(A) has quashed assessment order. [S. 115JB, 143(3)]