Don't take the exam.
3. Advanced Mathematics B of Chinese Academy of Sciences only takes advanced mathematics, and of course it will be deeper.
4. Personally, I think Huang Xiankai and Cao Xianbing's NPC review materials are better. After all, they are experts in Chinese Academy of Sciences, but this book is more expensive. I suggest going to the library to borrow one, just read the high number part and do more other materials. I have recommended it three times, Chen Wendeng's, Li Yongle's and Dr. Zhao's. Although I didn't play very well, I got 10.
5. Yes, they are all the central propositions of the Academy of Sciences.
If you want to enter the Academy of Atmospheric Sciences, report to the Academy of Atmospheric Sciences if you have the strength. If you have a good job, you should generally apply to a slightly worse institution, such as the Institute of Environment and Engineering in cold and arid areas. I wish you success!