结合材料，运用联系的观点，说明各国通过沟通合作等方式共同构建网络空间命运共同体的合理性。

阅读下面短文，在空白处填入一个适当的词，或填入括号中所给单词的正确形式。

    A poor farmer had a friend ____was famous for the wonderful apple tree he grew.    

    One day, his friend ____(give) the farmer a young apple tree and told him to plant it. The farmer was pleased with the gift, but he did not know where____(plant) it.    

    He was afraid that if he planted the tree near the road, strangers would steal the fruit. If he planted the tree in one ____his fields, his neighbors would come at night and steal some of the apples. If he planted the tree near his house, his children would take the fruit.____(final) he planted the tree in his wood. But ____(with) sunlight and good soil (土壤),the tree soon died.    

    Later the friend asked the farmer why he had planted the tree in such____ poor place. "What's the ____(different)? " the farmer asked____(angry). The friend answered, "If you planted the tree in the sunlight, at least ____could enjoy the fruit. Now you not only have robbed everyone of the fruit, but also you have destroyed (毁掉) a good apple tree !"   

某学生为了验证铁、锌、铜三种金属的活动性顺序，设计了四种方案：
①将Zn、Cu分别加入到FeSO₄溶液中；
②将Zn、Cu分别加入到ZnSO₄溶液中；
③将Zn分别加入到FeSO₄、CuSO₄溶液中；
④将Fe分别加入到ZnSO₄、CuSO₄溶液中．
其中可行的是        (    )

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