题目

A small plane crashed into a hillside five miles east of the city, _____all four people on board.  A. killed          B. killing           C. kills         D. to kill 答案：B 考查非谓语动词。此处现代分词做结果状语。从句意可知是结果，排除D表目的， 故选B.  若一个三角形的三边长均满足方程x2-6x+8=0，则此三角形的周长为    ．