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举一反三
【单选题】Isn’t it surprising that scientists have a better understanding of how many stars there are in the galaxy (银河系) than how many species there are on Earth Their estimates of global species diversity var...
A.
The soil and the deep sea belong to communities that haven’t been fully explored.
B.
It is surprising news wherever new species are discovered in the deep sea.
C.
About 90 million species are believed to live in the deep sea.
D.
A million species in the deep sea have been discovered and named.
【单选题】根据文意，天体物理学家发现的银河系“甘戈特里波”是一种（）。
A.
冰川一样的结构
B.
像“羽毛”一样的气体卷须
C.
连接银河系两条旋臂的固体星系结构
D.
冷一氧化碳气体云
【单选题】关于心包，叙述错误的是：
A.
包裹心和出入心大血管的纤维浆膜囊
B.
分为纤维性心包和浆膜性心包
C.
浆膜心包分脏、壁两层
D.
浆膜心包的脏壁两层之间形成心包腔
E.
以上都对