Your brain glue being what it is, work on the problems on a regular basis until the test.
Divide your study materials over a periods of time to do it all twice and then recap with a review. When solving problems, use pencil and write everything down, just don't look at it and believe that you know it.
Keeping track of the units on the test is very important. They are happy to mix cfm, cc's, pico's and nanos.
Answers may look like this
A. .001 uc/l
B. .00000001 pci/cc
So the message here is, don't just look for a number match to be sure you have the right answer. You gotta do the work every time.
And lastly, when I opened my test, the very first question blew me away, couldn't do it, I moved on and did everything else.
Don't let a couple of questions kick your mental butt, but study to be able to answer everything