题目内容
第(31)到(35)题中使用的3个数据表：“学生”表、“课程”表和“成绩”表的结构如下： “学生”表：学号C(8)，姓名C(8)，性别C(2)，系名(10)，出生日期D “课程”表：课程编号C(4)，课程名称C(12)，开课系名C(10) “成绩”表：学号C(8)，课程编号C(4)，成绩Ⅰ SQL查询语句：SELECT 课程名称，开课系名，COUNT (学号) AS 选修人数；FROM 成绩，课程；WHERE 课程．课程编号=成绩．课程编号；GROUP BY 课程名称；HAVING COUNT(*)＞3语句所表示的含义是( )。
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Don’t spend more on the promotion than the product.
10（）
2005年1O月，某外贸公司出口一批硅锰，海关按照出口税则给予免税放行。一年后发现该单位出口的不是硅锰而是硅锰铁合金，是应征出口税的货物。海关不应追征已漏征的税款。（）
Only three strategies are available for controlling cancer: prevention, screening and treatment. Lung cancer causes more deaths than any other types of cancer. A major cause of the disease is not (21) known; there is no good evidence that screening is much helpful, and treatment (22) in about 90 percent of all cases. At present, therefore, the main strategy must be (23) . This may not always be true, of course, as for some other types of cancer, research (24) the past few decades has produced (or suggested) some importance in prevention, screening or treatment.(25) , however, we consider not what research may one day offer but what today’s knowledge could already deliver that is not being delivered, then the most practicable and cost-effective opportunities for (26) . premature death from cancer, especially lung cancer, probably involve neither screening nor improved (27) , but prevention.This conclusion does not depend on the unrealistic assumption that we can (28) tobacco. It merely assumes that we can reduce cigarette sales appreciably by raising prices or by (29) on the type of education that already appears to have a (30) effect on cigarette assumption by whitecollar workers and that we can substantially reduce the amount of tar (31) per cigarette. The practicability of preventing cancer by such measures applies not only in those countries, (32) , the United States of America, because cigarette smoking has been common for decades, 25 to 30 percent of all cancer deaths now involves lung cancer, but also in those where it has become (33) only recently. In China, lung cancer (34) accounts for only 5 to 10 percent of all cancer deaths. This is because it may take as much as half a century (35) the rise in smoking to increase the incidence to lung cancer. Countries where cigarette smoking is only now becoming widespread can expect enormous increase in lung cancer during the 1990’s or early in the next century, (36) prompt effective action is taken against the habit-indeed, such increase is already plainly evident in parts of the (37) .There are four reasons why the prevention of lung cancer is of such overwhelming importance: First, the disease is extremely common, causing more deaths than any other type of cancer now (38) ; Secondly, it is generally incurable; Thirdly, effective, practicable measures to reduce its incidence are already reliably known; and finally, (39) tobacco consumption will also have a substantial (40) on many other diseases. 32().
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