(5)On receipt of the return, the Assessing Officer shall—(a)assess the income referred to in sub-section (2); and(b)determine the sum payable as tax thereon at the rate or rates in force applicable to the total income of a company which has not made the arrangements referred to in section 393(1) (Table: Sl. No. 7) and such sum shall be payable by the master of the ship.