Calculate the ionic strength and the activity coefficients for $C{a}^{2+}$ and $N{a}^{+}$in the following solution:

$\backslash$table$[[$Ion$,$Conc. $($mg$/$L$)],[C{a}^{2+},58\mathrm{.}0],[M{g}^{2+},85],[N{a}^{+},10\mathrm{.}1],[F{e}^{2+},0\mathrm{.}33],[C{O}^{2-},0\mathrm{.}41$ as CaCO$3$