First of all, I will provide the explanation of the term détente. Detente refers to a situation or policy that involves easing in political relationships, after a period of tensions.
In the context of the Cold War, the US adopted the policy of detente which put an end to the hostilities between the Easter and Western blocs. This was a result of the domestic reforms that the URSS implemented within its territory and economy which eventually resulted in the end of Communism in Europe and to the dismantling of the Soviet Union.
The thermometer was known to be significant because it was the first time that humans actually got hold of reading specific temperatures. The thermometer is also commonly used in various different situations. It's used to measure the heat/cold outside, the temperature of food, a human's temperature, and used to measure in science experiments. Those are simply a few examples. Hope this helped :))
Racial oppression and prejudice, fitting into the cultural normalities and societal standards, finding a job, possibly learning the language which they are not fluent in, etc.
It is a diary/record/manuscript, hope that helps you!
