Molality \( (m) \) of \( 3 \, \mathrm{M} \) aqueous solution of \( \mathrm{NaCl} \) is:(Given: Density of solution \( = 1.25 \, \mathrm{g \, mL^{-1}} \), Molar mass in \( \mathrm{g \, mol^{-1}} \): \( \mathrm{Na\!-\!23, \, Cl\!-\!35.5} \))
\( 3.85 \, \mathrm{m} \)
\( 2.90 \, \mathrm{m} \)
\( 2.79 \, \mathrm{m} \)
\( 1.90 \, \mathrm{m} \)