Here are some recommended problems from chapters 3 and 4 of the textbook to look over, as preparation for Midterm #1.   Of course, the more problems you have time to do, the better.  The textbook site has hints for some of them, if you get really stuck.

Chapter 3:
R-3.2
R-3.3
R-3.6
R-3.8
R-3.9
R-3.10
R-3.11
R-3.19
R-3.27
R-3.31
R-3.32
R-3.34
C-3.4
C-3.7
C-3.13

Chapter 4:
R-4.1
R-4.3
R-4.6
R-4.8
R-4.9
R.4.11
R-4.14
R-4.15
R-4.16
C-4.1
C-4.2
C-4.3
C-4.4
C-4.6
C-4.8
C-4.14