#feedback Small detail, but "none" is a singular personal pronoun; "If none of the answers look right" should be, "If none of the answers looks right."

#feedback "Blind" refers to when the person on whom the experiment is being performed is unaware of whether they're in the test or control group, whereas "double blind" is when neither the experimenter nor "experimentee" is aware of the group in which the "experimentee" is placed. You might've already known that and not bothered to mention it, haha.