题目内容

A 任何查询语句都可以用 union 来连接
B union 只连接结果集完全一样的查询语句
C union 是筛选关键词，对结果集再进行操作。
D union 可以连接结果集中数据类型及个数相同的多个结果集。

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写出题下图所示Windows任务栏各部分的名称。

根据下列材料回答问题。
铁道部为了安排下一年度的春运，制订并开展了一项统计调查，要求各铁路分局报送各路段当年的春运统计资料。
根据上述资料回答下列问题：
铁道部组织实施的这项统计调查应当是（）。

破碎机传动电机温升应＜80℃。（)

When you walk into a National Forest, you really believe you are the first person who has ever been here. Funny thing is, you are not.
These forests have been used for over a hundred years. From this timber stand, settlers used wood to build their homes. And ties were cut for the railroad. Hard to believe, isn't it？
But that's the Miracle of the Forest. With careful management these forests have renewed themselves, year after year, providing us with all kinds of benefits. And that's why we call them "Forever Forests".
Come to see for yourself! And get involved with the new "Forests For Us" program and tell people all about the Miracle of the Forest.
For more information write: Forest for US, P.O. Box 2000, Washington, DC 20013.
Miracle of the Forest
Duration that has been used:【46】.
Usage of the forest: 1.【47】for the building of houses
2.【48】for the railroad
The reason that we call them "Forever Forests":
1.【49】themselves with careful management
2. providing us with lots of【50】year after year