d
\(\text { Given } 9 \mathrm{MSD}=10 \mathrm{VSD}\)

\(\text { mass }=8.635 \mathrm{~g}\)

\(\mathrm{LC}=1 \mathrm{MSD}-1 \mathrm{VSD}\)

\(\mathrm{LC}=1 \mathrm{MSD}-\frac{9}{10} \mathrm{MSD}\)

\(\mathrm{LC}=\frac{1}{10} \mathrm{MSD}\)

\(\mathrm{LC}=0.01 \mathrm{~cm}\)

\(\text { Reading of diameter }=\mathrm{MSR}+\mathrm{LC} \times \mathrm{VSR}\)

\(=2 \mathrm{~cm}+(0.01) \times(2)\)

\(=2.02 \mathrm{~cm}\)

\(\text { Volume of sphere }=\frac{4}{3} \pi\left(\frac{d}{2}\right)^3=\frac{4}{3} \pi\left(\frac{2.02}{2}\right)^3\)

\(=4.32 \mathrm{~cm}^3\)

\(\text { Density }=\frac{\text { mass }}{\text { volume }}=\frac{8.635}{4.32}=1.998 \sim 2.00 \mathrm{~g}\)