d
\(\rho \, = \,\frac{M}{V} = \frac{M}{{{L^3}}}\)

\(\Rightarrow \,\frac{{\Delta \rho }}{\rho } = \frac{{\Delta M}}{M} + \frac{{3\Delta L}}{L}\)

\(\Rightarrow \,\frac{{\Delta \rho }}{\rho } = 3+2\times 3=9\%\)