题目

（08年大连24中文） 现有同一型号的汽车50辆，为了了解这种汽车每耗油1升所行路程的情况，要从中抽取5辆汽车做在同一条件下进行耗油1升所行路程的实验，得到如下数据（单位：km）：11，15，9，12，13，则样本方差是                     （    ）       A．20                      B．12                       C．2                        D．4缺词填空(共10空；每空l分，计l0分)根据短文内容和首字母提示，在下文空格处填入适当的词使短文完整。在答题卡标有题号的横线上，写出空缺处各单词的正确形式。(每空一词)Tragedy(悲剧) hit Shanghai on the last day of the year 2014. A stampede(踩踏) killed at l__1._ 36 people and 47 were hurt during New Year’s Eve celebrations on the Bund(外滩), a f__2.___ tourist attraction of the city.The Shanghai government said that large crowds started the stampede just before midnight. It was not c_3.__ so far what caused the disaster. Xinhua said that many of the injured were students.A stampede can h_4.__ anywhere where there is a large crowd. The Ministry of Education (教育部) has given out the instructions for teenagers to keep s__5.__.If people around you started to p__6. __, stand still and t__7._ to hold onto something, or stay in a c__8._ until the crowd leaves.If you f__9._ down in a moving crowd, cover your head with both h__10.__. Lean to one side, curl (蜷曲)your body and bend your legs.