You got that right about the tough ass curve. With the RC fucking me over going -2 on the rest of the test was still not enough to bail me out.
#5 focus on what is sufficient/necessary for a bacteria to qualify as a commensal. Benefit vs no benefit between M.T(no benefit - correct answerchoice) vs H.P(benefit- in stimulus) = critical deciding factor as one by default fails to compare as it fails to be a commensal by definition, whereas H.P this is not so clear cut.
#13 - I hope you had this down to A and B. The main premise in support it "you're already happy --> therefore, you may as well quit." Here, my gut told me that happiness can vary based on the amount of effort/time/sacrifice/etc. is required to achieve anything in this world. You losing your job and being unemployed is certainly going to cause more unhappiness than dealing with the shit you need to deal with on the job and getting $$$. I think B is trying to get at the assumption A makes explicit -- but someone else should clarify this.
#15 - Says journ. action of Y(cynicism) cannot be causing X(causing public to believe people are assholes) because journalists have always been doing Y. The premise here is that because an action has always been occurring, it cannot be causing this current result of people believing X. Clearly, there is no need to assume that because something has always happened, that it has not always resulted in X.
#23 - This one was annoying. I guess, because the main purpose of SG = social cohesion, if you can find an alternative to serve the main purpose, that could resolve the discrepency. If they said the main purpose was to achieve familial bonding, maybe an answer that said that families went hunting together to achieve FB would resolve the discrepency. On some tough questions, they often put in main reason/primary factor/etc. to pinpoint where the strongest support is, and what is in need of explaining/resolving.
#6 - Look at Patty's argument. It qualifies her position to being most Jap.People did not fear ninjas. Look at T's point of wealthy people showing signs of fear. Limiting T's argument to a minority of wealthy people allows patty to counter T's counter of her argument most effectively because most people can still not give a crap about fearing ninjas.
#12 - I think here the scope of the argument is just that offering free shipping --> 25% increase in mail order sales. It has nothing to do with competition among companies. It is a simple cause effect relationship and you should look for a no cause -- no effect in AC A. With D, it seems like this would weaken the argument a bit, as it seems like competing with the policies of competitors caused the sale increase, presenting an alternative that gives no reason to believe the cause was limited to the specific change in policy, which could have been an effect of AC D.
#15 - the stimulus's study compares people who did similar amounts of typing so A is contradicting a premise and therefore not helping resolve anything.
# 18 - I hope you got this down to C and E. This question required the best explanation for why shore environments were less than perfect for achieving the evolution of brain anatomy. The mechanism for evolution was, according to stim, a high -calorie diet. If E was true, the cost-benefit to achieivng the requirement for brain evolution would be less than optimal compared to other environments. C is too weak, in that it offering more resources than they do today could be one apple in the middle of a forest in dino-time vs. the forest having no apples today. It needs to explain why shore environments were not as perfect as they seemed to be relative to other environments, and E does this.
#22 - I got this down to C and D. Is this a new question type? I could use some help with this one as well

Edit: I think D is wrong because it does not say at least partly altruistic, to match the stimulus? I am too worried about my RC right now to figure this out today, but if I do later on I will let you know