取分别编导的锥形瓶4个，并做如下处理（不同锥形瓶所加的相同物质是等量的）瓶号1234内容物清水、金鱼清水、金鱼、金鱼藻清水、金鱼、金鱼藻、河泥清水、金鱼、金鱼藻、河泥条件见光密闭见光密闭见光密闭黑暗密

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取分别编导的锥形瓶4个，并做如下处理（不同锥形瓶所加的相同物质是等量的）

瓶号	1	2	3	4
内容物	清水、金鱼	清水、金鱼、金鱼藻	清水、金鱼、金鱼藻、河泥	清水、金鱼、金鱼藻、河泥
条件	见光密闭	见光密闭	见光密闭	黑暗密闭

请分析哪一个锥形瓶中的金鱼生存时间最长（）

A：1号

B：2号

C：3号

D：4号

上一题下一题 0.0难度选择题更新时间:2019-07-08 04:38:52

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C

同类题5

If someone is lost in a forest( 森林 ), he needs only study the trees around him carefully to find his way. On this half of the earth, he will find that the side of the tree with the most leaves and branches(树枝 ) is the south side. Also, by checking the tops of the trees, he will find that they lean(倾斜 ) to the south too.
Another sign( 标志物) for him to know where he is going is found in the bark.( 树皮) That is brighter on the south side.The remanining(树桩 ) of a cut tree is also a finder, for its rings can give him another sign. The rings will be thinner on the south side and thicker on the north side.
One more sign: some very small plants grow at the foot of a tree and they point to the north.

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