The questions are picked from a pool randomly so they are always different every time you take them. However, tons of quesitons may appear to be almost exactly the same with just a few small differences. The technologies covered though and the frequency they are covered are supposedly the same each time. I'm not 100% positive but the sims don't change each time you take the taste. I think those are only overhauled once every few months.
Word of caution, you shouldn't be studying brain dumps. They are waste of time and many think they are morally reprehensible. Learn the material the right way and take the test when you are ready.