题目

 It is necessary that parents should ________ the responsibility of helping their children develop legal awareness. A. take on       B. carry on        C. look on         D. keep on 答案：A做匀减速运直线运动的物体经4s后停止，若在第1s内位移是14m，则最后1s的位移是（　　）A．3.5mB．3mC．2mD．1m