A standard cell is balanced at 150 cm. height of a potentiometer wire. If this cell is shunted by a resistance of 2 Ω, the balanced position is obtained at 100 cm. length. The internal resistance of the cell will be :

(1) 2 Ω

(2) 1 Ω

(3) 0.66 Ω

(4) 0.1Ω