2. Re-read the derivation of the equations for planetary surface temperature and planetary atmospheric temperature under the framework of a one-layer energy-balance model as laid out in Lesson 5. After re-reading the derivation, write the two aforementioned equations, and, for each equation, explain what each variable in the equation is. Summarize also the assumptions behind the derivation; in other words, explain what a one-layer EBM is and how it differs from a 0-D EBM. This is as straightforward as it seems, but this problem is here to ensure that you understand the underlying concepts because they are referenced often in climate science. Report your discussion on the answer sheet