The terminal voltage of the battery, whose emf is $$10 \mathrm{~V}$$ and internal resistance $$1 \Omega$$, when connected through an external resistance of $$4 \Omega$$ as shown in the figure is:

A wire of length '$$l$$' and resistance $$100 \Omega$$ is divided into 10 equal parts. The first 5 parts are connected in series while the next 5 parts are connected in parallel. The two combinations are again connected in series. The resistance of this final combination is:

Two heaters $$A$$ and $$B$$ have power rating of $$1 \mathrm{~kW}$$ and $$2 \mathrm{~kW}$$, respectively. Those two are first connected in series and then in parallel to a fixed power source. The ratio of power outputs for these two cases is:

Choose the correct circuit which can achieve the bridge balance.