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问题 单项选择题

下列关于施工支护的拆除正确的是（）。

A.喷护混凝土拆除时，应自下而上、分区分段进行

B.用镐凿除喷护混凝土时，面对面使镐

C.用大锤砸碎喷护混凝土时，周围不应有人站立或通行

D.锤击钢钎，抡锤人应站在扶钎人的侧面，使锤者应戴手套，锤柄端头应有防滑措施

答案

参考答案：C

单项选择题 B1型题

气虚，统摄无权，冲任不固所导致的妇科疾病是（）

A.带下病

B.崩漏

C.经间期出血

D.胎动不安

E.滑胎
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单项选择题

The blue of the sea is caused by the scattering of sunlight by tiny particles suspended in the water. Blue light, being of short wavelength, is scattered more efficiently than light of longer wavelengths. Although waters of the open ocean are commonly some shade of blue, green water is commonly seen near coasts, especially in tropical or subtropical regions. This is caused by yellow pigments being mixed with blue water. Phytoplankton are one source of the yellow pigment. Other microscopic plants may color the water brown or brownish-red. Near the shore, silt or sediment in suspension can give water a brownish hue. Outflow of large rivers can often be observed many miles offshore by the coloration of suspended soil particles.Marine phytoplankton (Greek for "plant wanderers") are microscopic single-celled plants that include diatoms, dinoflagellates, coccolithophorids, green algae, and blue-green algae, among others. The growth of these organisms, which photosynthesize light, depends on a delicate balance of nutrient enrichment via vertical mixing, which is often limited by the availability of nitrogen and light. Diatoms are one-celled plants with patterned glass coverings. Each glass, or silicon dioxide box, is ornamented with species-specific designs, pits, and perforations making them popular with microscopists and, more recently, electron scanning microscopists.

Green water near coastlines is almost always caused by________.

A．sand color

B．red pigments in coastal waters

C．blue pigment

D．reflected light and yellow pigment from plant life
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