An open capillary tube is lowered in a vessel with mercury. The difference between the levels of the mercury in the vessel and in the capillary tube is $\mathrm{\Delta h}=\mathrm{ }\text{4.6} \mathrm{mm}$. The radius of curvature of the mercury meniscus in the capillary tube will be (surface tension of mercury is $\text{0.46} \mathrm{N} {\mathrm{m}}^{-1}$ of mercury is $\text{13.6} \mathrm{g} {\mathrm{cm}}^{-3}$)