Scores for exam 4 are now up. As I feared, the average is about 15% less than exam 3. Exam 3 average score was about 90%, exam 4 average score was about 76%.
And to be honest, it was a pretty easy exam, all but 2 of the proofs were pretty trivial, and the other two weren't really that tough.
Anyway, my advice is to continue working on proofs. The final exam is coming up, and is cumulative. There will be proofs corresponding to the material in chapters 3 and 4. And there will be fewer trivial proofs on the final. So get those proof skills honed.
Rick