Match the following according to conversion by heat :

Liquid oxygen at $50\  K$ is heated to $300\  K$ at constant pressure of $1\  atm$. The rate of heating is constant which of the following graphs represents the variation of temperature with time

What is vapourization ? What is normal boiling point ?

A child running a temperature of $101\,^{\circ} F$ is given an antipyrin (i.e. a medicine that lowers fever) which causes an increase in the rate of evaporation of sweat from his body. If the fever is brought down to $98\,^{\circ} F$ in $20$ minutes, what is the average rate of extra evaporation caused, by the drug (in $g/min$). Assume the evaporation mechanism to be the only way by which heat is lost. The mass of the child is $30\; kg$. The spectfic heat of human body is approximately the same as that of water, and latent heat of evaporation of water at that temperature is about $580\; cal \;g^{-1}$.

Two substances $A$ and $B$ of equal mass m are heated at uniform rate of $6\, cal s^{-1}$ under similar conditions. $A$ graph between temperature and time is shown in figure. Ratio of heat absorbed ${H_A}/{H_B}$ by them for complete fusion is