Answer:
. A closed system allows only energy transfer but no transfer of mass. Example: a cup of coffee with a lid on it, or a simple water bottle. ... In reality, a perfectly isolated system does not exist, for instance hot water in a thermos flask cannot remain hot forever.
I think the correct answer from the choices listed above is option A. The structural level of a protein least affected by a disruption in hydrogen bonding is the primary level. The other levels are very much affected by hydrogen bonding. Hope this answers the question.
I believe the answer is A the 1st one
3.6 x 10^-4
I am writing this sentence because the answer does not reach the 20 character limit. Thank you have nice day! :D Cx :P
