下列说法正确的是[] A．根据反应SiO2+2CSi +2CO↑，说明碳的非金属_爱下问搜题

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问题选择题

下列说法正确的是[ ]

A．根据反应SiO₂+2CSi +2CO↑，说明碳的非金属性强于硅的非金属性

B．同周期从左至右，元素形成的氢化物的沸点逐渐升高

C．化合物中显+4价的元素一定是第ⅣA族元素

D．离子化合物NaN₃和Na₃N中所含的化学键类型不同

答案

答案：D

多项选择题

既可通过输血感染，又可通过性接触传染的病毒（）

A.甲型肝炎病毒

B.乙型肝炎病毒

C.丙型肝炎病毒

D.HIV

E.梅毒

补全对话，情景问答

根据所给句子. 选择最佳的应答语。每个选项只能用一次。

(    )1. Do you think it important to exercise?
(    )2. What do you do on Sunday?
(     )3. Is she too young to make her own decisions?
(     )4. Are you going to leave school at the end of the term?
(    )5. What does your brother do in the evening?

A.  Yes, she is.
B.  I guess so.
C.  Watching TV.
D.  Yes, this is my last year at school.
E.  No, this is my last year at school.
F.  He chats on the Internet.