I have a question! Well, two questions, actually. How do the comments get sorted in the threads, what decides what comment is first? And the same for my feed, how are the posts sorted?

You're making it out to be a lot more difficult than it actually is. What this test does is see if people try to get a "no" answer before actually making a guess. Like ooli said, the point is to see if you can overcome your confirmation bias. It's not so much important to actually get the answer right, as to not be afraid of making tests that are wrong, instead of just doing the ones that confirm your hypotheses.