The temperature on a Fahrenheit temperature scale that is twice the temperature on a Celsius temperature scale is: (in $^{\circ} F$)

Assertion $(A)$: Rapidly changing temperatures can be measured by thermocouples.
Reason $(R)$: The thermal capacity of the junction of a thermocouple is very small.

$A$ Centigrade and a Fahrenheit thermometer are dipped in boiling water. The water is then cooled until the Fahrenheit thermometer reads $140 ^\circ F$. The corresponding drop in temperature as recorded by the Centigrade thermometer is ...... $^\circ C$.

Mercury is often used in clinical thermometers. Which one of the following properties of mercury is not a reason for this?

$A$ faulty thermometer reads $5^{\circ}C$ in melting ice and $95^{\circ}C$ in steam. The correct temperature on the absolute scale will be $.........K$ when the faulty thermometer reads $41^{\circ}C$.

What is called absolute zero temperature?