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问题 填空题

两只形状相同的烧杯，分别盛有质量相同的水和酒精，试用两种方法判断出水和酒精，（不能用品尝的方法），方法一：_____________________；方法二：_________________。

答案

方法一.采用相同质量比较体积，体积大的为酒精，质量一定的酒精密度小体积大；

方法二. 闻气味法，有气味的为酒精；

方法三.点燃法，取一点点燃能燃烧的是酒精；

方法四.敞开放在空气中，更易挥发的是酒精；

方法五.沾一点在手上，感觉更凉的是酒精。

（答案不唯一，任选两种方法即可）

阅读理解
阅读理解。
     Different types of maps have different uses.
Tourist maps, for example, have signs (标志) to
show places of interest in an area. When tourists
read these maps, it is easy for them to find where
to go and what to see in a place and it is easy for
them to go and find their ways to these places.
    Road maps show large areas so that people can
plan long journeys. Different types of roads are
given different numbers. For example, if you want
to go to Wood Green, you just follow No. 621
Road and keep looking at the road signs.
    Distribution maps (分布图) use colors or signs to
show facts about an area. For example, where
different languages are spoken, how many people
live in an area, how cold and hot some places are,
or whether a place is short of water.
     Some maps, such as railway maps, use straight
lines to show everything. This is easy for people
to read. Trains are fast. People don't have to think
about small places they go past. They just need to
know the two ends of their trips.
1. Jim wants to visit some places of interest. Which map does he need most?
A. A road map.
B. A tourist map.
C. A distribution map.
D. A railway map.
2. How can you tell different roads on Road maps?
A. By finding the numbers.
B. By using different colors.
C. By using straight lines.
D. By looking at the road signs.
3. Which of the following can Distribution maps tell us?
A. How to get to Germany.
B. How to plan a long journey.
C. Which place is short of water.
D. Where a famous museum is.
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单项选择题

当SART收到X波段的导航雷达时，会（）

A、闪光周期加快，无声音

B、闪光周期不变，有声音

C、闪光周期加快，有声音

D、视何种型号而定
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