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【简答题】
(6分) 现有以下六种物质:硝酸钾、小苏打、铝、石墨、天然气、氮气。根据下列要求用化学式填空: (1)可充入食品包装袋用于防腐的是 ; (2)发酵粉的主要成分之一是 ; (3)可作干电池电极的是 ;       (4)可作燃料,其主要成分是 ; (5)其组成元素是地壳中含量最高的金属元素 ;(6)可作复合肥料的是 。
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【单选题】The class is unusual_______ the students are all over fifty and none of them attended the middle
A.
23. The class is unusual_______ the students are all over fifty and none of them attended the middle school when they were young. A.in how
B.
in what
C.
in which
D.
in that
【简答题】显示单价大于出版社为“江苏大学” 所有书籍价格的图书信息
【单选题】The students are all gone.Because of the bad weather, the teacher permitted them _____ early.
A.
leave
B.
to have left
C.
to being leaving
D.
to leave
【判断题】电压比较器的阈值电压是使集成运放同相输入端电位和反相输入端电位相等的输入电压。
A.
正确
B.
错误
【单选题】关系模型中,下列关于候选键说法正确的是 _______
A.
可由其值能惟一标识该关系中任何元组的一个或多个属性组成
B.
可由多个任意属性组成
C.
至多由其值能唯一标识该关系任何元组的一个属性组成
D.
其余都不是
【简答题】x=0.1010,y=0.0011,求x+y。
【判断题】在离体实验中,给家兔小肠孵育的外液中加入肾上腺素,可抑制小肠运动。
A.
正确
B.
错误
【简答题】The students are all late ________ the top students.
【简答题】The students are all ____________ (期待) going to the commencement of their graduation.
【单选题】_______the class, the students are all noisy. [     ]
A.
Begin with
B.
At the begin
C.
At the beginning
D.
At the beginning of
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