When a block of iron floats in mercury at 0^oC, a fraction $k_1$, of its volume is submerged, while at the temperature ${60}^0 C$, a fraction k₂, is submerged. If the
coefficient of volume expansion of iron is ${\mathrm{\gamma }}_{\mathrm{Fe}}$ and that of mercury is${\mathrm{\gamma }}_{\mathrm{Fe}}$ , then the ratio ,k₁ / k₂ can be expressed as

• A

  $\frac{1+60{\mathrm{\gamma }}_{\mathrm{Fe}}}{1+60{\mathrm{\gamma }}_{\mathrm{Hg}}}$

• B

  $\frac{1-60{\mathrm{\gamma }}_{\mathrm{Fe}}}{1-60{\mathrm{\gamma }}_{\mathrm{Hg}}}$

• C

  $\frac{1+60{\mathrm{\gamma }}_{\mathrm{Fe}}}{1-60{\mathrm{\gamma }}_{\mathrm{Hg}}}$

• D

  $\frac{1+60{\mathrm{\gamma }}_{\mathrm{Hg}}}{1+60{\mathrm{\gamma }}_{\mathrm{Fe}}}$