Oxygen boils at $-183^{\circ}C$. This temperature is approximately ....... $^{\circ}F$.

The temperature of a substance increases by $27^{\circ}C$. On the Kelvin scale,this increase is equal to ........ $K$.

Two temperature scales $A$ and $B$ are related by $\frac{A-42}{110}=\frac{B-72}{220}$. At which temperature do the two scales have the same reading?

What is the change in temperature on the Fahrenheit scale and Kelvin scale,if an iron piece is heated from $30\ ^oC$ to $90\ ^oC$?

Answer the following:
$(a)$ The triple-point of water is a standard fixed point in modern thermometry. Why? What is wrong with taking the melting point of ice and the boiling point of water as standard fixed points (as was originally done in the Celsius scale)?
$(b)$ There were two fixed points in the original Celsius scale as mentioned above,which were assigned the numbers $0^{\circ}C$ and $100^{\circ}C$ respectively. On the absolute scale,one of the fixed points is the triple-point of water,which on the Kelvin absolute scale is assigned the number $273.16\; K$. What is the other fixed point on this (Kelvin) scale?
$(c)$ The absolute temperature (Kelvin scale) $T$ is related to the temperature $t_c$ on the Celsius scale by $t_c = T - 273.15$. Why do we have $273.15$ in this relation,and not $273.16$?
$(d)$ What is the temperature of the triple-point of water on an absolute scale whose unit interval size is equal to that of the Fahrenheit scale?

At what temperature in $^\circ F$ is the density of water maximum?