一支标有“220V  1 00W”的电烙铁，为使电烙铁正常工作时电功率为100W，而在保温时，电烙铁的功率为25W，使之不会完全冷却．为此，某同学设计了如图所示的电路，其中，S为单刀双掷开关，L为一只额定电压为220V的灯泡．下列说法中正确的是（　　）

关于电流与电源，下列说法中正确的是（   ）

人体是一个统一的整体．下图是人体神经系统调节某些生命活动的示意图．请据图回答：

2010年4月14日，青海省玉树县发生7.1级地震，造成重大人员伤亡和财产损失。一方有难，八方支援。灾情发生后，江苏黄埔再生资源利用有限公司、博宥投资管理集团有限公司、内蒙古鄂尔多斯永隆有限责任公司通过中华慈善总会共向青海玉树地震灾区捐赠超过3000万元救援物资，这些物资：
①凝结了人类劳动，具有价值 ②是劳动产品，具有使用价值
③是没有价值的赠品         ④没有用于交换，不是商品

阅读理解
　    Many people have to work on the weekend. Some people do not mind. Others think it is terrible.
　　One man thinks that working on the weekend can be dangerous. He is Graham Coates. Mr Coates works in an office in Brighton, England.
　　On Saturday, May 24, 1986, he went to the office to do some work. When he got on the lift(电梯), it stopped between floors. Mr Coates could not get out of the lift. He started to shout, but no one heard him. Then Mr. Coats remembered that it was a holiday in England. No one was going to come to work until Tuesday.
　　There was nothing for him to do. He had to wait until one of his workmates came to work and found him. With nothing to eat or drink, Mr Coats ended up sleeping for most of the day.
　　Now Mr. Coates says, "I only use lifts if they have telephones in them."