Properties of Solids and Liquids: JEE Main 2021 Physics question

Suppose you have taken a dilute solution of oleic acid in such a way that its concentration becomes 0.01 cm³ of oleic acid per cm³ of the solution. Then you make a thin film of this solution (monomolecular thickness) of area 4 cm² by considering 100 spherical drops of radius ${\left( {{3 \over {40\pi }}} \right)^{{1 \over 3}}} \times {10^{ - 3}}$ cm. Then the thickness of oleic acid layer will be x $\times$ 10^$-$14 m. Where x is ____________.