I haven't seen GRE's math, so I'll take a look at it on my laptop. It is purely a discussion topic, and I hope you will criticize it. The first question has been given, the range is 4, and x is greater than 0, so isn't x the root of 5? The root number 5 is indeed greater than 2. So you can choose one ... I think so. As for the second question, my idea is, (7.8-6.5+7.5-6.9+4.9-4.1) *100 = 270. So it's similar to B ... but I don't know what it has to do with the pie chart on the left ... Is the pie chart the next question?