What is the value of $\Lambda _m^o$ $(NaCl)$ at $298 \ K$?

Resistivity of $0.5 \ M$ electrolytic solution is $10 \ \Omega \ cm$. Find the molar conductivity of the solution.

Write the formula to calculate conductivity by using a conductivity cell.

Resistance of a decimolar solution between two electrodes $0.02 \ m$ apart and $0.0004 \ m^2$ in area was found to be $50 \ \Omega$. Specific conductance $(\kappa)$ is $:$

The resistance of $1 \, M$ acetic acid is $250 \, \Omega$. The cell constant of the conductivity cell is $1.15 \, \text{cm}^{-1}$. What is the equivalent conductivity (in $\Omega^{-1} \, \text{cm}^2 \, \text{equiv}^{-1}$) of $1 \, N$ acetic acid?

Solutions of two electrolytes $A$ and $B$ are diluted. The $\Lambda_m$ of $B$ increases $1.5$ times while that of $A$ increases $25$ times. Which of the two is a strong electrolyte? Justify your answer.