The resistances of the four arms P, Q, R and S in a Wheatstone's bridge are 10 ohm, 30 ohm, 30 ohm and 90 ohm, respectively. The e.m.f. and internal…

The resistances of the four arms P, Q, R and S in a Wheatstone's bridge are $\displaystyle 10$ ohm, $\displaystyle 30$ ohm, $\displaystyle 30$ ohm and $\displaystyle 90$ ohm, respectively. The e.m.f. and internal resistance of the cell are $\displaystyle 7$ Volt and $\displaystyle 5$ ohm respectively. If the galvanometer resistance is $\displaystyle 50$ ohm, the current drawn from the cell will be :