【单选题】Can you show your stamps ____ your classmates? [ ]
【简答题】with rule astigmatism
【单选题】According to the description of a patient: +2.75/-2.00×90,, what kind of astigmatism is it?
B.
against-rule astigmatism
【判断题】Astigmatism occurs when the curvature of one side of the cornea is steeper or rounder than the other side.