题干

 下列应用和相应的原理(用化学方程式表示)及基本反应类型都正确的是(  )


A:用熟石灰制生石灰   CaO+H2O═Ca(OH)2    化合反应

B:实验室用氯酸钾和二氧化锰混合物制取氧气 2KClO32KCl+3O2↑    分解反应

C:用酒精作燃料 C2H5OH+3O22CO2+3H2O     置换反应

D:用Al(OH)3中和胃酸  2Al(OH)3+3H2SO4═Al2(SO43+6H2O      复分解反应

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B

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    Some people will do just about anything to save money. And I am one of them. Take my family's last vacation. It was my six-year-old son's winter break form school, and we were heading home from Fort Lauderdale after a week-long trip. The flight was overbooked, and Delta, the airline, offered us $400 per person in credits to give up our seats and leave the next day. I had meetings in New York, so I had to get back. But that didn't mean my husband and my son couldn't stay. I took my nine-month-old and took off for home.

    The next day, my husband and son were offered more credits to take an even later flight. Yes, I encouraged—okay, ordered—them to wait it out at the airport, to "earn" more Delta Dollars. Our total take: $1,600. Not bad, huh?

    Now some people may think I'm a bad mother and not such a great wife either. But as a big-time bargain hunter, I know the value of a dollar. And these days, a good deal is something few of us can afford to pass up.

    I've made a living looking for the best deals and exposing (揭露) the worst tricks. I have been the consumer reporter of NBC's Today show for over a decade. I have written a couple of books including one titled Tricks of the Trade: A Consumer Survival Guide. And I really do what I believe in.

    I tell you this because there is no shame in getting your money's worth. I'm also tightfisted when it comes to shoes, clothes for my children, and expensive restaurants. But I wouldn't hesitate to spend on a good haircut. It keeps its shape longer, and it's the first thing people notice. And I will also spend on a classic piece of furniture. Quality lasts.