今天西安的大雁塔（下图）就是当年玄奘大师保存佛经的地方，这些佛经是从哪国取回的（    ）

实验室用氯酸钾和二氧化锰的混合物制取氧气，某次实验中固体的质量变化如下：

（1）生成氧气的物质的量为　0.15　mol．

（2）求参加反应的氯酸钾的物质的量．（根据化学方程式列式计算）

（3）根据题目中所给条件，判断氯酸钾是否已经完全分解？　否　（填“是”或“否”）．

    This is a map of our school. There are1 buildings in our school: a library, an office building, a class building, a dinging hall and a sports hall. The library is2the left of the class building. There3many books in the library. We study in the class building, and after class, we often read books in the4. Our teachers work in the5 . This is a building6 twelve offices. Four teachers are in one office. Our school is old,7we have a big sports hall. We8 in it. What's your favourite9? Let's play it in the sports hall. I 10 my school very much. It's very good.

下列说法中正确的是（   ）