Re the written.
Besides having the knowledge there is a method in taking the test. Make sure to read the question very carefully and think about the answer for a moment, then look at the 4 choices. There may be a key word that is the relevant one. Did they say agl or msl, or statue or nautical or gallons or pounds, etc. Often the key word may be in the answer, making one correct and one only seem correct. Two answers may be way off and you can narrow it down to the other two, to find the one that is more right. Take enough time to be sure.
If you have a few that you really don't know, you can leave them blank and come back to them, I think, but don't fail to answer all of them. If it involves a calculation, after you get your answer, take a moment to see if it makes sense.
It is easy to pass, but I know people that have made 100%. I missed one question on mine, something about airport lighting, and it still bugs me.
Good luck, it will be good for you to have it done.