A bakelite beaker has volume capacity of 500 cc at 30°C. When it is partially filled with V_m volume (at 30°C) of mercury, it is found that the…

A bakelite beaker has volume capacity of $\displaystyle 500$ cc at $\displaystyle 30$°C. When it is partially filled with $\displaystyle \mathrm{V}_{\mathrm{m}}$ volume (at $\displaystyle 30$°C) of mercury, it is found that the unfilled volume of the beaker remains constant as temperature is varied. If $\displaystyle \gamma_{(\text {beaker })}=6 \times 10^{-6}{ }^{\circ} \mathrm{C}^{-1}$ and $\displaystyle \gamma_{(\text {mercury })}=1.5 \times 10^{-4}{ }^{\circ} \mathrm{C}^{-1}$, where $\displaystyle \gamma$ is the coefficient of volume expansion, then $\displaystyle \mathrm{V}_{\mathrm{m}}$ (in cc ) is close to \_\_\_\_.