I am trying to memorize all of them. I took calculus 1 and 2, so I know most of them already. I just need to brush up on a few and work on my speed. I tend to go into a stupor after a few hours of studying and then taking practice exams, so my brain just dies towards the end of these 4 hour practice exams. Nonetheless, I find QR very doable in the practice exams. I just hope the real DAT is the same, if not easier. The calculations in topscore totally takes most of my time imho.