如图1是初中实验常见装置，请回答：

（1）写出图中标号为a、b的仪器名称：a____；b____．
（2）实验室中用过氧化氢溶液和二氧化锰混合制取氧气，发生装置应选用图中____（填字母代号）装置，收集氧气可选用____（填字母代号）装置，该反应的化学方程式为____．
（3）某活动小组用加热草酸晶体制得的CO做还原氧化铜的实验，设计了如图2的装置．（化学方程式：H₂C₂O_4˙2H₂O  CO₂↑+CO↑+3H₂O）
回答下列问题：
①加热分解草酸晶体应选用的发生装置为____（填上面常见装置图中的字母代号）．
②能证明氧化铜被还原的现象是____ ．装氧氧化钠溶液的洗气瓶能否与装浓硫酸的洗气瓶对调____（填“能”或“不能”）．
③处理尾气的方法可采用____（填一种即可）．

下列地区黄河流经，山地冰川广布，农业以畜牧业为主的是（　　）

某地洪水为患，消息上报朝廷后，皇帝一方面交代工部尽快抢修溃决的堤防，勿使水患继续扩大；另一方面责成户部尽快调度粮食，运往灾区，赈济灾民。幕僚根据皇帝之意，写成诏书，经皇帝确认无误后，直接送至工部、户部等单位执行。这是下列哪个时期的制度

    Have you ever been to the world's smallest bookstore?

    The World's Smallest Bookstore, whose official name is just these three words, sits quietly about 100 miles northeast of Toronto.

    The bookstore is about 10 feet by 10 feet，so it is easy to imagine how tiny it really is. The bookstore is open 24 hours a day. Inside the bookstore are various books, especially literary books and classic authors' works. So if you are looking for something less popular, you may get a bit disappointed there.

Another special feature of this bookstore is that each book only costs three dollars. All the expenses are paid on the honor system, which means buyers should make a note of what they've bought and leave their money by themselves. So the tools of the trade in this bookstore are quite simple: pens, papers, light bulbs and a label-maker.

    In order to catch passers-by's attention, the billboards (广告牌) of the bookstore are several times bigger than the store itself. With these large eye-catchers, many people are willing to stop by and have a visit.