已知空气可以传播声音,请设计一个简易实验,证明固体也能够传播声音。请写出实验所需

题型:实验题

问题:

已知空气可以传播声音,请设计一个简易实验,证明固体也能够传播声音。请写出实验所需器材、实验步骤及实验结论。(要求设计的实验要有可行性,符合安全原则)  

(1)实验器材:_______________________________________________ ; 

(2)实验步骤:_______________________________________________ ;  

(3)实验结论:________________________________________________。

考点:声音的传播
题型:实验题

给甲、乙、丙三人打电话,若打电话的顺序是任意的,则第一个打电话给甲的概率是______.

题型:实验题

持续性枕横(后)位对胎儿的主要影响是()

A.常出现胎儿窘迫和新生儿窒息使围生儿死亡率增高

B.可导致新生儿低血糖

C.新生儿呼吸窘迫综合征发生率增加

D.导致新生儿红细胞增多症

E.导致新生儿呕吐

题型:实验题

Part 1: Self-introduction


·The interlocutor will ask you and your partner questions about yourselves. You may be asked about things like "your hometown", your interests ", "your career plans ", etc.

Part 2: Presentation


·The interlocutor gives you two photographs and asks you to talk about them. for about one minute. The examiner then asks your partner a question about your photographs and your partner responds briefly. Then the interlocutor gives your partner two photographs. Your partner talks about these pictures for about one minute. This time the interlocutor asks you a question about your partner’s photographs and you respond briefly.

Part 3: Collaboration


·The interlocutor gives you andyour partner a list of topics. Both of you need to choose one to discuss together. The interlocutor may join in the conversation and ask you questions, but you and your partner are expected to develop the conversation.

Topic 1:

How to Make the Best Use of Money

Topic 2:

Skills on Making Bargains

Topic 3:

Methods to Prevent Burglary

Topic 4:

Relationship Between Man and Animals

Topic 5:

Virtues of Being Young and Being Old

题型:实验题

最大多数人的利益和全社会全民族的积极性创造性,对党和国家事业的发展始终是最具有决定性的因素。( )

题型:实验题

干阑式民居主要分布在我国的( )。

A.西北沙漠地带
B.东南沿海地带
C.东北地区
D.西南地区

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