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问题 选择题

某地几种氮肥的销售价格如下：硫酸铵[（NH4）2SO4]800元/吨；尿素[CO（NH2）2]2400元/吨，碳铵[NH4HCO3]470元/吨；硝酸铵[NH4NO3]1000元/吨．某菜农用1000元钱去购氮肥，为使所购氮肥中氮总量最多，应选购（　　）

A．硫酸铵

B．尿素

C．碳铵

D．硝酸铵

答案

答案：C

填空题

根据课文内容，解释下面句子的意思。

1．  使弈秋诲二人弈，其一人专心致志，惟弈秋之为听；一人虽听之，一心以为有鸿鹄将至，思援弓缴而射之。

                                                                                                                                                          

                                                                                                                                                          

2． 一儿日：“日初出沧沧凉凉，及其日中如探汤，此不为近者热而远者凉乎？”

                                                                                                                                                          

                                                                                                                                                           

3．一儿曰：“我以日始出时去人近，而日中时远也。”

                                                                                                                                                           
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单项选择题

读《周易》的最高的层面是什么？（）

A.原道之书

B.休养之书

C.易变之书

D.占卜之书
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