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问题 单项选择题

下列各组物理量中，都是矢量的是（）

A.位移、时间、速度

B.速度、速率、加速度

C.加速度、速度的变化量、速度

D.路程、时间、位移

答案

参考答案：C

解析：

矢量是既有大小又有方向的物理量，如位移，速度，加速度，速度变化量；标量是只有大小没有方向的物理量．如时间速率，路程等，所以选C

填空题

阅读短文，用方框中所给单词的适当形式填空，使短文意思通顺、完整。每空限填一词，每词限用一次。有两个词多余。

   

There was a small village near a mountain. People there loved their village very much and they grew many 小题1:      on the mountain. Water in the rivers was very clear and the 小题2:  was clean. People lived a poor life, but they were very 小题3:    . After a few years, some people in the village started to cut down trees to 小题4:    for money. There were some people from cities 小题5:   to visit the village. People began to kill some wild animals as 小题6:      to treat (招待) the visitors. Of course, they made lots of money. But小题7:     knew what the village would be like in the future.

As time went on, there were fewer plants and animals and the water became 小题8:     . The visitors became fewer and fewer. Several years later, people there knew they must stop destroying (破坏) 小题9:   . They would like to live a happy life as before, so they began to小题10:  new plants. They hoped the village would become as beautiful as before.
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单项选择题

编写教材（教科书）的直接依据是（）。

A.课程计划

B.课程目标

C.课程标准

D.课程说明
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