A. a bicycle chain is an example of a compound machine
Answer:
aluminum will be the best insulator...coz it have a high resistance
Answer: The original temperature was

Explanation:
Let's put the information in mathematical form:





If we consider the helium as an ideal gas, we can use the Ideal Gas Law:

were <em>R</em> is the gas constant. And <em>n</em> is the number of moles (which we don't know yet)
From this, taking
, we have:
⇒
Now:
⇒