题目

To make a living ,they are willing to _______many of the disadvantages of city life such as crime .heavy traffic ,and pollution. A. put up    B. put off C. put up with    D. put away 答案：C 如图所示，A、B叠放在水平桌面上，今用水平拉力F作用于B，但没有拉动，则物体B共受到几个力作用 [　　] A．5 B．6 C．4 D．3