题目

This is my twin sister. Not only she but also I _____________good at dancing. A . am B . are C . is D . aren't 答案：A如图,在正四棱柱ABCD-A1B1C1D1中,AB=1,AA1=,点E为AB上的动点,则D1E+CE的最小值为(　　)A．2B．C．+1D．2+