某同学用已调好的托盘天平称量物体的质量，操作情况如图A所示，其中错误的是
（1） ；（2） .
（1）被称物体和砝码位置放颠倒了、（2）用手拿砝码．
题目分析：天平的正确使用：把天平放在水平台上，游码移到标尺左端的零刻度；调节天平的平衡螺母使天平的横梁平衡；物体放在天平的左盘，砝码放在天平的右盘，使天平的横梁重新平衡；物体的质量等于砝码的质量加游码对应的刻度值．天平使用的注意事项：不要把化学药品和潮湿的物体直接放在天平盘上；要用镊子夹取砝码，不能用手拿砝码；砝码要及时放回砝码盒，要轻拿轻放．对照图中信息可知错误为（1）被称物体和砝码位置放颠倒了、（2）用手拿砝码．
Hello, everyone. Here is something important for everyone going to London next month. As you know, you are going to stay with a family for two weeks. Now, the most important thing is money. You should take about $530 with you. I think it will be enough for everyone. Then, when you arrive, your new family will meet you. You must remember to wear a red shirt, so the family will find you easily. They’ve been told you all wear red shirts. You’ll also need to take with you 4 photos of yourself and, of course, it’s very important that you take the school letter. While you’re there, if you have any problems, you can call Leech School Office. I’ll give you the office phone number now: it’s 580-4436 and the person to ask for is Mrs. Belcher…She’s in the office from nine o’clock in the morning until five in the afternoon every day. OK. That’s everything. Have a good journey!
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