Monatomic and Diatomic

[Mike Vinci 2B]

Hello,
When working through the problem 8.31, it uses the calculation q=n*Cp*delta T and q=n*Cv*delta T for the second part. Given that Kr(g) is monatomic, I know that I can replace Cp and Cv with 3/2R and 5/2R respectively, however I'm confused about if I were given a diatomic model, Kr2(g). In the book it says for "linear molecules, Cp and Cv are 5/2R and 7/2R. What I would like to clarify is if linear molecules stated on page 281 can also imply that they are diatomic. If this is the case, would we be explicitly told if the gas we are dealing with is monatomic or diatomic/linear?

Thanks.

[Nicole Jacobs 1C]

Our TA told us that we would be given a diatomic or monatomic obvious molecule, or if it is not obvious, it will be given explicitly in the question