The limiting molar conductivity of KCl is $149.8\mathrm{S}\mathrm{c}{\mathrm{m}}^2\mathrm{mo}{\mathrm{l}}^{-1}$ and the transport number of $\mathrm{K}{}^{+}$ in very dilute KCl is $0.4907$. The limiting molar conductivity of $\mathrm{KNO}{}_3$ is $144.9\mathrm{S}\mathrm{c}{\mathrm{m}}^2\mathrm{mo}{\mathrm{l}}^{-1}$. Which of the following statement(s) is/are correct?

1. A${\lambda }^{\circ }(\mathrm{K}{}^{+})=73.5\mathrm{S}\mathrm{c}{\mathrm{m}}^2\mathrm{mo}{\mathrm{l}}^{-1}$
2. B${\lambda }^{\circ }(\mathrm{NO}{}_3{}^{-})=71.4\mathrm{S}\mathrm{c}{\mathrm{m}}^2\mathrm{mo}{\mathrm{l}}^{-1}$
3. CThe transport number of $\mathrm{K}{}^{+}$ in very dilute $\mathrm{KNO}{}_3$ is about $0.507$
4. D$\mathrm{NO}{}_3{}^{-}$ has a higher ionic mobility than $\mathrm{Cl}{}^{-}$