A hollow cylindrical conductor has length of 3.14 m, while its inner and outer diameters are 4 mm and 8 mm respectively. The resistance of the conductor is $$n\times10^{-3}\Omega$$. If the resistivity of the material is $$\mathrm{2.4\times10^{-8}\Omega m}$$. The value of $$n$$ is ___________.

The current I flowing through the given circuit will be __________A.

An electrical bulb rated 220 V, 100 W, is connected in series with another bulb rated 220 V, 60 W. If the voltage across combination is 220 V, the power consumed by the 100 W bulb will be about _______ W.

As shown in the figure, a potentiometer wire of resistance $$20 \,\Omega$$ and length $$300 \mathrm{~cm}$$ is connected with resistance box (R.B.) and a standard cell of emf $$4 \mathrm{~V}$$. For a resistance '$$R$$' of resistance box introduced into the circuit, the null point for a cell of $$20 \,\mathrm{mV}$$ is found to be $$60 \mathrm{~cm}$$. The value of '$$R$$' is ___________ $$\Omega .$$