Column $I$ gives some devices and Column $II$ gives some processes on which the functioning of these devices depends. Match the devices in Column $I$ with the processes in Column $II$.

Column $I$	Column $II$
$(A)$ Bimetallic strip	$(p)$ Radiation from a hot body
$(B)$ Steam engine	$(q)$ Energy conversion
$(C)$ Incandescent lamp	$(r)$ Melting
$(D)$ Electric fuse	$(s)$ Thermal expansion of solids

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

$A$ water cooler of storage capacity $120$ litres can cool water at a constant rate of $P$ watts. In a closed circulation system (as shown schematically in the figure),the water from the cooler is used to cool an external device that generates constantly $3 \text{ kW}$ of heat (thermal load). The temperature of water fed into the device cannot exceed $30^{\circ}\text{C}$ and the entire stored $120$ litres of water is initially cooled to $10^{\circ}\text{C}$. The entire system is thermally insulated. The minimum value of $P$ (in watts) for which the device can be operated for $3$ hours is (Specific heat of water is $4.2 \text{ kJ kg}^{-1} \text{K}^{-1}$ and the density of water is $1000 \text{ kg m}^{-3}$)

$A$ block of ice at $0^{\circ}C$ falls from a height of $1 \ km$ onto an insulating surface. If all its kinetic energy is converted into heat,what fraction of the ice will melt? (Take $g = 10 \ m/s^{2}$ and latent heat of fusion of ice $L = 3.36 \times 10^{5} \ J/kg$)

What are freezing and freezing point?

Heat needed to convert $1 \ kg$ of ice at $0^{\circ} C$ to steam at $100^{\circ} C$ is