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【单选题】
民间航海家属于哪个朝代人?A.
B.
唐代
C.
宋代
D.
元代
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皮皮学刷刷变学霸
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【简答题】简述水体中农药的来源。
【单选题】The presence of microorganisms that produce a toxin causes seawater to turn brownish red, a phenomenon known as a red tide. Sea otters do not feed in areas where clams, their main source of food, have...
A.
In some of the areas where red tides occur, neither clams nor sea otters are indigenous species.
B.
The presence of sea otters in a given area has a significant effect on which other marine organisms are to be found in that area.
C.
When seawater in an area unaffected by red tide is artificially dyed brownish red, sea otters do not feed on the clams in that area.
D.
If the clams in a given area are contaminated with toxins, sea otters move to other areas in search of food.
E.
Although very small amounts of the toxin produced during a red tide are not harmful, large doses can be fatal to animals the size of sea otters.
【多选题】以下属于强迫症状的表现有:
A.
有意识地自我强迫和反强迫并存，二者强烈冲突使患者感到焦虑和痛苦。
B.
仪式动作可使精神痛苦减轻，单社会功能受损。
C.
意识到强迫与反强迫的冲突异常性，但无法摆脱。
D.
在癫痫、心脏病首次发作后害怕再发作，感到紧张焦虑。
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