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【单选题】
From the beginning rivers have played an important part in the life of man. Man of the earliest times used the rivers as a means of traveling. Today rivers still serve as a great waterway for the transport and people. In ancient times, man settled near rivers or on river banks and built up large empires. Water is the Nature's most precious gift to man. Man needs water to irrigate his crops, to cook and to wash. In nations all over the world rivers mean life and wealth. They feed and clothe the nations around them. Water is also a source of energy and power. Man constructs huge dams across the river to control the water for irrigation and get the energy needed to drive generators. The electrical power is then directed to homes, cities, factories and television stations. Man uses water each day. His main source of water comes from reservoirs, which in turn get their water from the rivers. Rivers also bring down soil and minerals from the mountains and deposit them on the plains building up rich river deltas for raising plants and crops. Fresh water life in rivers or in lakes fed by them provide man with food. In a small way rivers help to keep man in good health and provide for his amusements. Various forms of water sports keep man strong and healthy. Rivers have run on this earth long before man. Man's future ability to live is uncertain, but rivers will flow on forever. Rivers have been important to man______.
A.
since the last century
B.
for a very long time
C.
since a few hundred years ago
D.
since a few years ago
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A.
筹资限制较少
B.
降低公司资金成本
C.
增强公司筹资能力
D.
降低公司财务风险
【简答题】药品经营企业必须执行
【多选题】相对于发行债券筹资而言,对企业而言,发行股票筹集资金的优点有( )。
A.
增强公司筹资能力
B.
降低公司财务风险
C.
降低公司资金成本
D.
筹资限制较少
【简答题】药品经营企业必须遵守
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A.
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B.
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C.
分辨率
D.
准确度
【单选题】质谱仪器的性能指标中用于评价相邻质量数离子是否分开的指标是( )
A.
分辨率
B.
灵敏度
C.
精密度
D.
质量范围
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A.
正确
B.
错误
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A.
正确
B.
错误
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A.
正确
B.
错误
【单选题】关于麻醉前用药的药理作用,下列叙述正确的是()
A.
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B.
哌替啶有时可出现呼吸“遗忘”现象
C.
地西泮可解除恐惧、引导睡眠和遗忘作用
D.
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E.
吗啡不能直接抑制呼吸中枢
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