题目

尺规作图：（用圆规和直尺作图，不写过程，但要保留作图痕迹）已知：如图，直线AB与直线BC相交于点B，点D是直线BC上一点．求作：点E，使直线DE∥AB，且使线段BE长度最短． 答案：解：如图①作∠MDB=∠ABC，②作BN⊥DM交DM于E．点E即为所求．_______ did the winner of the bicycle race ride? At the speed of 40 kilometers an hour.A.How longB.How farC.How fastD.How much