在实验探究过程中和现实生活中，一定要注意安全．下列有关做法中正确的是（ ）
A．洒在桌面上的酒精燃烧起来，立即用湿抹布或沙子扑灭
B．夜间发现家中液化石油气泄露，立即开灯查明泄露原因
C．带上手电筒就放心进入久未开启的菜窖或深井
D．一氧化碳还原氧化同时应先加热，再通一氧化碳，防止一氧化碳污染环境
A、洒在桌面上的酒精燃烧起来，立即用湿抹布扑盖，可以有效的隔绝空气，灭火，操作正确，故A正确；
B、液化石油气是可燃气体，与空气混合见明火易发生爆炸，发现家中液化石油气泄露，立即开灯查明泄露原因是错误的，故B错误；
C、久未开启的菜窖或深井中易贮存较多的二氧化碳，进入前要点燃蜡烛进行实验，带手电筒进入错误．故C错误；
D、一氧化碳还原氧化同时应先通一氧化碳，再加热，防止一氧化碳与空气混合加热发生爆炸，故先加热，再通一氧化碳，错误．
故选A、
Water, it’s a problem for the whole world. A bottle (瓶) of water may not seem like much to us, 1 it can help the people who live in drought-hit (遭受旱灾的) areas in China. In the past few months, many places in southwest China have 2 a serious drought. There has been very little 3 since last autumn. More than 20 million people are 4 trouble finding safe drinking water. After learning about the drought, many people around the country helped by 5 away water, money and other resources (资源) to the people there. Last week, the Young Pioneers and the Communist Youth League in China called on (号召) each student to give one bottle of water to the drought-hit area. In Xi’an, 900 students bought over 100 bottles of water 6 their pocket money. They also wrote their 7 on the bottles. “I hope you get more rain there. I hope you are happy.” A bottle of water isn’t much, but thousands of bottles will be very 8 . The serious drought has also made students 9 the importance of saving water. One student said, “I have decided to take a shower twice a week 10 every day to save water.”
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