If the temperature of a body increases by $30^{\circ}C$ on the Celsius scale,then the increase in temperature on the Fahrenheit scale is .... $^oF$.

$A$ centigrade and Fahrenheit thermometer are dipped in boiling water. The water temperature is lowered until the Fahrenheit temperature observed is $140^{\circ} F$. At that time the temperature registered by the centigrade thermometer is (in $^{\circ} C$)

Mercury thermometers can be used to measure temperatures up to ........ $^oC$. (in $^oC$)

What is a thermometer? What is a gas thermometer? Write its characteristics.

The temperature of a body on the Kelvin scale is found to be $X \; K$. When it is measured by a Fahrenheit thermometer,it is found to be $X \; ^\circ F$. Then $X$ is:

Maximum density of $H_2O$ is at the temperature .......... $^\circ F$.