①黄铜      ②氧化铜      ③铁锈      ④钢．

“心中有党，心中有民，心中有责，心中有戒”，谷文昌身上，集中体现了一名县委书记应具备的“四有”品质。他为党分忧、为民谋利、敢于担当、清廉公正，用生前事身后名，回答共产党人“入党为了什么，当了干部做什么，身后留下什么”的人生课题，展现了政去人声后、丰碑在人间的崇高魅力。谷文昌的行为(　　)

①践行了***的宗旨

②反映了公民的权利与义务是统一的

③体现了共产党员的先锋模范作用

④启示我们要将个人利益与国家利益相结合

如图所示，M是一小型理想变压器，接线柱a、b接在电压u＝311sin314t(V)的正弦交流电源上，变压器右侧部分为一火警报警系统原理图，其中R₂为用半导体热敏材料制成的传感器，电流表A₂为值班室的显示器，显示通过R₁的电流；电压表V₂显示加在报警器上的电压(报警器未画出)，R₃为一定值电阻．当传感器R₂所在处出现火警时，以下说法中正确的是（    ）

完形填空

    Mr. Smith lived in a big city. When he retired(退休), he bought a small 1in a village near the sea. He2it and hoped to live a quiet life in this house.

    But to his great surprise, many visitors came to see his house in summer holidays, for it was the most 3building in the village. From morning to night there were 4outside the house. They kept looking 5the rooms through the windows and many of them even went into Mr. Smith's garden. This was too much for Mr. Smith. He decided to ask the visitors to 6. So he put a notice (告示) on the window. The notice said, “If you want7it, come in and look round. Price: twenty dollars.” Mr. Smith was sure that the visitors could8coming, but he was wrong. More and more visitors came and Mr. Smith had to 9every day taking them around his house.“I came here to 10not to work as a guide,” he said angrily. In the end, he sold the house and moved away.