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问题 单项选择题 B1型题

上述哪项指标属于饮用水毒理学指标（）。

A.硫酸盐

B.浑浊度

C.游离性余氯

D.镉和砷

E.痢疾杆菌

答案

参考答案：D

解析：1.在饮用水消毒过程中，为保证消毒效果，加氯量必须超过水的需氯量，使其在氧化和杀菌后还能剩余一些有效氯，称为“余氯”。试验证明接触时间达30分钟，游离性余氯在0.3mg/L以上时，对肠道致病菌、钩端螺旋体、布氏杆菌等均有杀灭作用。我国《生活饮用水卫生标准》（GB5749-2006）中规定游离性余氯的标准值为出厂水中的含量不得大于4mg/L且不得小于0.3mg/L，管网末梢水中不得小于0.05mg/L。2.镉、砷等元素为毒性元素，在体内具有明显的蓄积作用而产生危害。

单项选择题

Geography is the study of the relationship between people and the land. Geographers compare and contrast various places on the earth. But they also (51) beyond the individual places and consider the earth as a whole. The English word geography means "to describe the earth. " (52) geography books focus on a small area like a town or city. Others deal with a state, a region, a nation, or an (53) continent. Many geography books deal with the whole earth. Another (54) to divide the study of geography is to distinguish between physical geography and cultural geography. The former focuses on the natural world; the (55) starts with human beings and studies how human beings and their environment act (56) each other. But when geography is considered as a single subject, (57) branch can neglect the other. A geographer might be described as one who observes, records, and explains the (58) between places. If all places (59) alike, there would be little need for geographers. We know, however, that no two places are exactly the same. Geography, (60) is a point of view, a special way of looking at place.

59().

A.being 

B.are 

C.be 

D.were
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单项选择题

我国商业银行目前普遍实行的资产负债管理是：（）

A.资产管理理论

B.负债管理理论

C.资产负债比例管理

D.“实存实贷”信贷资金管理办法
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