题目

如图所示，楔形物体B静止在粗糙的斜面上,其质量为M，斜面倾角为。一质量为m的小物块A静  止在斜面上。用恒力F沿斜面向上拉小物块，小物体A仍然静止在斜面上。下列说法正确的是 A.没有施加恒力F时，地面对楔形物体B的支持力为Mg B.施加恒力F时，地面对楔形物体B的摩攘力为 C.施加恒力F时，地面对楔形物体B的支持力为 D.施加恒力F时，地面对楔形物体B的摩擦力为8、     When the population of the town began to ____(1) from poisoning, the police came to find the cause of the poison. They thought someone was ____(2) the people on purpose but no one knew how it was possible. Some people suspected that the ____(3)   was poisoned. It was a popular food everyone ate and it could have possibly made everyone sick. Anyone who had taken _____(4) of pork would throw it out. Even the poorest of the poor wouldn’t eat it. Signs were _____(5) on poles and letters were sent to everyone to ____(6) people of the park. Shortly afterwards, even policemen in high positions were also getting _____(7).      Soon it became political and popular._____(8) rushed to the town to talk about politics and promised how they would find the solution if they were _____(9).Everyone was so _____(10) that they didn’t care about politics. They went to the post office to mail posts out asking for _____(11).The poor town didn’t know how to deal with the _____(12).One day, a well-known man from New York came to the town with a huge box _____(13) many instruments and his possessions. He went to ____(14) and the port made measurements. He was quiet and polite. Then one day he made a speech at a newspaper meeting room to _____(15) his findings.      “I am sorry to _____(16)your water supply is so heavily polluted; it is poisoned. I know who has been poisoning you for such a long time._____(17) is you who have been poisoning yourselves with pollution. A great deal of_____(18) has been thrown into the water day by day. No one here has taken good care of the environment. It is no _____(19) that you have been sick.”______(20) at the news, the people present were lost in thought. 1) A) struggle            B) suffer           C) experience          D) benefit 2) A) saving                    B) killing           C) poisoning           D) robbing 3) A) port                      B) porridge        C) pork               D) potato 4) A) possession         B) care            C) notice              D) hold 5) A) delivered           B) posted          C) put up             D) shown 6) A) inform             B) remind          C) warn               D) tell 7) A) worried                   B) angry           C) upset              D) sick 8) A) Architects                 B) Physicians       C) Politicians          D) Environmentalists 9) A) elected            B) saved           C) helped             D) rescued 10) A) sick             B) fine            C) happy              D) disappointed 11) A) advice           B) help           C) cure               D) medicine 12) A) action            B) situation        C) solution             D) suggestion 13) A) including          B) accepting       C) containing          D) equipped with 14) A) parks             B) schools         C) hospitals            D) pools 15) A) display           B) discuss         C) declare             D) announce 16) A) talk              B) speak          C) say                D) tell 17) A) That             B) It              C) This               D) One 18) A) rubbish           B) fish          C) pork               D) dust 19) A) question          B) reason        C) wonder            D) longer 20) A) Shocked          B) Excited       C) Tired              D) Frightened 评卷人 得分 二、选择题 （每空？ 分，共？ 分）