A 6.90 M solution of KOH in water contains 30% by mass of KOH.Calculate the density of the KOH solution ?[Molar mass of KOH=$56g mol^{-1}$]

Question

$\begin{array}{1 1}1.288gcm^{-3}\\2.288gcm^{-3}\\3.288gcm^{-3}\\4.288gcm^{-3}\end{array}$