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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.
气体的体积（V）与时间（t）关系如右图。反应中镁和铝的