阅读下面短文，根据其内容完成后面各项任务
    In the Charles E. Johnson Elementary School in New York, there is a special radio. It gives people warnings（警报）about bad weather.
One day, there came a sound from the radio. This sound brought the piece of news:a heavy storm was coming. William Tom, principal（校长）of the school, asked teachers to bring children indoors and put them in a safe place at once.
   Minutes later, the storm came. However, because of the warning of the radio and the quick work of the principal, no one was hurt.
“The radio really did work very well.             （我们对它的工作感到很高兴），”William Tom said. “The parents were as well.”
    The U.S. government hopes there will be more such success stories. It plans to give this kind of radios to all 97,000 public schools in the country.
    Every year, more than 10,000 big thunderstorms, 2,500 floods, 1,000 tornadoes（龙卷风）and some hurricanes（飓风）take place in the U.S., so the warning radios are very useful. They not only give people warnings about bad weather, but also give warnings about other dangerous things.

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下列实验操作中，完全正确的一组是（    ）

①用试管夹夹持试管时，试管夹从试管的底部向上套，夹在试管的中上部  ②给盛有液体超过试管容积$\frac{1}{3}$的试管加热   ③把鼻孔靠近容器口去闻气体的气味  ④将试管平放，用纸槽向试管里送入固体粉末，然后使试管竖立起来  ⑤取用放在细口瓶里的液体时，取下瓶塞倒放在桌面上，倾倒液体时，标签向着地面  ⑥将烧瓶放在桌面上，再将塞子用力塞上  ⑦用坩埚钳夹持加热后的蒸发皿  ⑧将滴管垂直伸进试管内滴加液体  ⑨稀释浓硫酸时，把水迅速倒进盛有浓硫酸的量筒中  ⑩检验装置的气密性时，把导管的一端浸入水中，用手掌握住容器或用酒精灯微热