a
\(M=(0.6 \pm 0.006) \; g\)

\(r=(0.5 \pm 0.005) \; mm\)

\(l=(4 \pm 0.04) \; cm\)

\(\rho=\frac{m}{V}\)

\(\Rightarrow \frac{\Delta \rho}{\rho}=\frac{\Delta m}{m}+\frac{2 \Delta r}{r}+\frac{\Delta l}{l}\)

(Volume of cylinder \(=\pi r^{2} l\) )

\(=\frac{0.006}{0.6}+\frac{2 \times 0.005}{0.5}+\frac{0.04}{4}\)

\(100 \times \frac{\Delta \rho}{\rho}=4 \times 10^{-2} \times 100\)

\(\frac{\Delta \rho}{\rho} \times 100=4 \%\)