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问题 填空题

在一个不透明的抽奖箱内装有20个形状、大小、质地完全相同的小球，其中只有4个小球标有中奖标志，则随机抽取一个小球中奖的概率是______．

答案

∵在一个不透明的抽奖箱内装有20个形状、大小、质地完全相同的小球，其中只有4个小球标有中奖标志，

∴随机抽取一个小球中奖的概率是：

4
20
=
1
5
．

故本题答案为：

1
5
．

改错题

下面文中共有10处语言错误，要求你在错误的地方增加、删除或修改某个单词。

增加：在缺词处加一个漏词符号（/\），并在该句下面写出该加的词。

删除：把多余的词用斜线（\）划掉。

修改：在错的词下划一横线，并在该词下面写出修改 后的词。

注意：1. 每处错误及其修改均仅限一词；

2. 只允许修改10处，多者（从第11处起）不计分。

例如：                                    

It was very nice to get your invitation to spend /\ weekend with you. Luckily I was 

the                        am

completely free then, so I’ll to say “yes”. I’ll arrive in Bristol at around 8 pm in Friday

on

evening.

 

Most of the large cities in the world have grown without plans, among that London is such a city.

Its streets wind its way and there is no reason or order to its street numbering system. Indeed,

no one but a practical taxi driver knows the whole of London. And before he gets his license, he

must first tour the city for month, street by street, and then take a test to prove that whether he can find

his way about. New York and Chicago grew in much the same way. They spread out like pouring water

expanding at all directions.

However, there are a few modern cities built strict according to detailed plans. The prime

example of a city planning and built from scratch in twentieth century is Brasilia, the new capital of

Brazil.
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选择题

下列日常生活中的物质变化或性质描述正确的是（　　）

A．化学家在环境问题上提出的最新构想是变废为宝，资源循环利用：燃料燃烧产物燃料，以上两个转化过程的变化均属于化学变化

B．网络、报纸、电视等媒体爆料的造假事件：用淀粉、蔗糖、奶香精等掺和成“奶粉”是化学变化

C．在厨房里，“在晾干的咸菜表面会出现白色晶体”，这属于化学性质

D．在衣柜里，“樟脑球渐渐消失”，这属于物理性质
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