Which solution of $NaNO_3$ will have maximum specific conductance in $N$?

The resistance of a $1 \, N$ solution of a salt is $50 \, \Omega$. The two platinum electrodes in the solution are $2.1 \, cm$ apart and each has an area of $4.2 \, cm^2$. Calculate the equivalent conductivity of the solution.

Calculate the molar conductivity of $0.2 \text{ M}$ $KCl$ solution at $298 \text{ K}$ given that the conductivity $\kappa = 0.0248 \text{ }\Omega^{-1} \text{cm}^{-1}$.

Calculate the molar conductivity of $CH_2ClCOOH$ at zero concentration if molar conductivities of $HCl$,$KCl$,and $CH_2ClCOOK$ at zero concentration are $4.2$,$1.4$,and $1.1 \ \Omega^{-1} \ cm^2 \ mol^{-1}$ respectively.

$0.2\% (w/v)$ solution of $NaOH$ is measured to have resistivity $870.0 \ m\Omega \ m$. The molar conductivity of the solution will be $........ \times 10^2 \ mS \ dm^2 \ mol^{-1}$. $(Nearest \ integer)$

Given below are two statements $:$
Statement $I :$ Mohr's salt is composed of only three types of ions$-$ferrous,ammonium and sulphate.
Statement $II :$ If the molar conductance at infinite dilution of ferrous,ammonium and sulphate ions are $x_1, x_2$ and $x_3 \ S \ cm^2 \ mol^{-1}$,respectively then the molar conductance for Mohr's salt solution at infinite dilution would be given by $x_1+x_2+2 x_3$
In the light of the given statements,choose the correct answer from the options given below $:$