What is gas thermometer is used for?

Assertion: Water is considered unsuitable for use in thermometers.

Reason: This is due to small specific heat and high thermal conductivity.

Represent the union of two sets by Venn diagram for each of the following.

$X=\{x | x$ is a prime number between $80$ and $100\}$

$Y=\{y | y$ is an odd number between $90$ and $100\}$

Give one word for each of the following: 

All the temperatures, from lowest to highest, which a thermometer can measure

Assertion: Gas thermometers are more sensitive than liquid thermometers.

Reason: Coefficient of thermal expansion of gases is more than liquid.

The diagram shows two liquid-in-glass thermometers.

Which is more sensitive? Explain how you can tell.

The temperature of the sun is measured with