I am good at taking these tests. For real, the best way is to slow it down and actually visualize what is being said, especially intruments, even if what you visualize isn't actually what is happening. For instance, for tenth thicknesses, I visualize the radiation going thru one tenth thickness of lead, and it looks like a graph in my mind, one side of the lead has a bunch of gray looking gammas high up on the wall, but when they pass thru, only about 10% of those gammas are left on the other side. Just a simple thing here, but hopefully you get my point, I don't need to think about tenth thicknesses anymore, I have a visualiztion that will work for remembering, even if it isn't really EXACTLY how things work. Don't memorize words ever, unless you have to, like nuclide of concern. But even with stuff like that, if you try to really get in to each important nuclide, like learning the 1/2 life, MeV of gamma, gas or solid, it will help when the test comes because you can reason out why it is the nuclide of concern. For instance, why is Ar-41 a nuclide of concern shortly after a reactor shutdown? Well, it has a longer halflife than N-16 (1.8hr vs 7 secs) and it has a big gamma, so since N-16 goes away really quickly and AR-41 is in the reactor coolant (I think it comes from acivation of AR-40, which is 1% of the air we breath, and is entrained in the coolant inertly). So Ar-41 hangs around for a while. There are a couple other reasons also, but I'm not writing a book here (almost

. Don't memorize only that AR-41 is a nuclide of concern 15 minutes after reactor shutdown, know why. If you are reading the material and you come upon a word you don't truly understand, look it up, take the time this one time. If you do that, in 5 years when it comes time to take the test again you won't stress and spend a whole lot of time going crazy, you'll already know it!