题目

A warm drink of milk before bed has long been the best choice for those wanting a good night’s sleep. But now a study has found it really does help people nod off—if it is milked from a cow at night.Researchers have discovered that “night milk” contains more melatonin(褪黑激素), which has been proven to help people feel sleepy and reduce anxiety.The study, by researchers from Seoul, South Korea, involved mice being fed with dried milk powder made from cows milked both during the day and at night.Those given night milk, which contained 10 times the amount of melatonin, were less act用若干个（个数不限）同样大小的含45°的三角尺拼成四边形，这些四边形内角度数有（　　）种不同情况． A、3B、4C、5D、6