题目

已知△ABC中,∶∶=1∶1∶,则此三角形的最大内角的度数是( ) A.120°          B.60°          C.90°          D.135°           答案:A 【解析】 试题分析:由三角形三边的比例,不妨设三边长分别为、、,最大内角即为所对的角;由余弦定理得,所以最大角为120°,故选D. 考点:余弦定理.When he came back, he found the bag he had ______________ over the seat was gone. A. left hanging              B. left to hang               C. left hung          D. to leave hanging
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