$A$ block of ice at $-12^{\circ} C$ is slowly heated and converted into steam at $100^{\circ} C$. Which of the following curves best represents the event?

Match the following :

Column-$I$	Column-$II$
$(a)$ Combined existence of liquid-gaseous state of substance.	$(i)$ Sublimation curve
$(b)$ Combined existence of solid-gaseous state of substance.	$(ii)$ Fusion curve
	$(iii)$ Vaporization curve

It is possible for a substance to coexist in all three phases in equilibrium,when the substance is at

$A$ solid cube of mass $m$ at a temperature $\theta_0$ is heated at a constant rate. It becomes liquid at temperature $\theta_1$ and vapour at temperature $\theta_2$. Let $s_1$ and $s_2$ be specific heats in its solid and liquid states respectively. If $L_f$ and $L_v$ are latent heats of fusion and vaporisation respectively,then the minimum heat energy supplied to the cube until it vaporises is

$A$ cylinder of mass $1\,kg$ is given heat of $20000\,J$ at atmospheric pressure. If the initial temperature of the cylinder is $20\,^oC$,then the work done by the cylinder will be .......$J$. (Given: Specific heat of cylinder $= 400\,J\,kg^{-1}\,^oC^{-1}$,Coefficient of volume expansion $= 9 \times 10^{-5}\,^oC^{-1}$,Atmospheric pressure $= 10^5\,N/m^2$,and density of cylinder $= 9000\,kg/m^3$)

If the ratio of densities of two substances is $5:6$ and the ratio of their specific heat capacities is $3:5$, then the ratio of heat energies required per unit volume so that the two substances can have the same temperature rise is