在应用速度分析实际问题时，下列说法正确的有（）。
A.当时间序列中的指标值出现0或负数时，不宜计算速度
B.速度指标的数值与基数的大小有密切关系
C.运用环比增长速度这一指标反映现象增长的快慢时，往往要结合水平指标的分析才能得出正确结论
D.环比增长速度时间序列中各期的基数相同
E.当时间序列的指标值出现0时适宜直接用绝对值进行分析
参考答案：A, B, C, E
解析：环比增长速度时间序列中，各期的基数不相同，故选项D错误。
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| On a cold winter day, I waited in line to see my hero, Jack Canfield, the author of The Success Principles During his talk, Jack 1 his wallet, pulled out a hundreddollar bill, and said, "Who wants this?" 2 shot up in the audience; people leaned forward to see whom Jack would 3 . But I jumped up, ran up the 4 to the stage, and grabbed the bill.As I was launching myself in the air, thoughts 5 through my mind-was I about to be humiliated (羞辱) in front of 800 people?Would they 6 security guards and take me from the stage? 7 my desire for bold action was louder than any 8 voice. As I got the bill from his hand, he said, "That's it!We can't wait for the 9 to come to us.We must take action to 10 what we want!" After his talk, I managed to formally meet Jack and boldly asked for his 11 email address.Over the next months, I sent him emails 12 my vision and dreams with him.He kindly emailed back lots of encouragement.But my life got 13 with other things.I stopped emailing Jack. A year later, my dreams had worn away.I thought Jack would inspire me into action, like a giant 14 that would show me the way. I emailed him, and then again-but got no 15 . As I sat down at my computer to check my emails, I 16 woke up.What was I doing?I was waiting!Now I remembered the crowd, most likely 17 that hundreddollar bill, while they sat 18 to their chairs. Usually we all have a "Jack" for whom we wait-whether it's a person, a place or a thing.We 19 believe the gifts of life are just around the corner, and that everything will come in a(n) 20 way.So we don't try.We give up. But as Wayne Gretzky said: "You'll always miss 100% of the opportunities you don't take!" So I stopped waiting and started my writing career. Now what are you waiting for? | ||||
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