题目

Jane is ________ girl and she is in Grade 1. A . a 8-years-old B . an 8-years-old C . a 8-year-old D . an 8-year-old 答案：D如图，△ABC中，∠BAC=90°，AB=3，AC=4，点D是BC的中点，将△ABD沿AD翻折得到△AED，连CE，则线段CE的长等于（ ） A.2B.C.D.