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草酸晶体的组成可用H2C2O4•xH2O表示,为了测定x值,进行如下实验:称取Wg草酸晶体,配成100.00mL水溶液.将25.00mL所配制的草酸溶液置于锥形瓶内,加入适量稀H2SO4后,用浓度为amol•L﹣1的KMnO4溶液滴定到KMnO4不再褪色为止.试回答:
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    Last year, I was on a plane with my friend, waiting for it to take off. The pilot's voice was heard throughout the plane: “Sorry for the delay, ladies and gentlemen. Our engines don't work. We are going to jump-start them. Once we get them going, we'll get up in the air and see what happens.”

    That was all he said. “See what happens? Shouldn't we have had a better plan than that?” At that point, I could only laugh nervously. One woman started crying: “Oh, no! We are going to crash!” There are sighs of desperation and anxiety, and we hadn't even taken off yet.

    The pilot even seemed unhappy. He told us one engine was working double time, and his plan was to get up in the air and see what happens! Then we did. We got up in the air, and what happened? Nothing. We arrived in Norfolk, and no sooner had the wheels touched down than applause burst out as everyone on the airplane breathed a sigh of relief.

    All too often, people stop achieving their goals just because they don't have a guaranteed result. But success will never be guaranteed. The best thing that you can do is to just get up in the air, and see what happens.

    If your aim is to build a business, then get up in the air and see what happens! Don't give yourself all the reasons why you can't. Do not wait until you have everything you need. You never will.

    If your goal is to start a friendship, say “Hello”, get up in the air and see what happens! The results could be very rewarding. If your goal is to learn a new skill, get up in the air and see what happens! It might not be as difficult as you think. It could be fun!