Q1: 'Cryogenics' is concerned with the generation & use of low temperature in the range of

ANS:A - 0°K to 123°K

The range of 0°K to 123°K is not typically associated with cryogenics. Cryogenics generally deals with much lower temperatures, typically below the boiling point of nitrogen (-196°C or 77 K) and often below the boiling point of helium (-268.9°C or 4.2 K). In the range from 0°K to 123°K, temperatures are above the boiling point of nitrogen and much higher than typical cryogenic temperatures. At 123°K, which is equivalent to approximately -150°C, most gases are still in their gaseous state, and cryogenic effects such as the liquefaction of gases are not observed. Therefore, the correct range for cryogenic temperatures is typically from 0°K to 273°K or 0°C to -273°C, encompassing the temperatures at which gases like nitrogen and helium liquefy and cryogenic phenomena are observed.