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问题 判断题

国际贸易合同中使用的fCA、CPT、CIP、DAf、DDU和DDP条款时，运输方式可以是铁路货物运输。（）

答案

参考答案：对

解答题
设f（x）=logag（x）（a＞0且a≠1）
（1）若f(x)=log
1
2
(3x-1)，且满足f（x）＞1，求x的取值范围；
（2）若g（x）=ax2-x，是否存在a使得f（x）在区间[
1
2
，3]上是增函数？如果存在，说明a可以取哪些值；如果不存在，请说明理由．
（3）定义在[p，q]上的一个函数m（x），用分法T：p=x0＜x1＜…＜xi-1＜xi＜…＜xn=q
将区间[p，q]任意划分成n个小区间，如果存在一个常数M＞0，使得不等式|m（x1）-m（x0）|+|m（x2）-m（x1）|+…+|m（xi）-m（xi-1）|+…+|m（xn）-m（xn-1）|≤M恒成立，则称函数m（x）为在[p，q]上的有界变差函数．试判断函数f（x）=log4(4x2-x)是否为在[
1
2
，3]上的有界变差函数？若是，求M的最小值；若不是，请说明理由．
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单项选择题

Once a man and his wife worked for an old man. There was a big box in the old man’s living room. The old man pointed to the box and said, "There’s only one thing you (1) do. Don’t open the box. " (2) saying this, he left his home.The woman said to her husband," There must be (3) expensive in the box. Let’s open it, shall we" Her husband said (4) to her. But the woman didn’t give up her (5) . One day, she decided to find out (6) was in it. Her husband didn’t stop her. She opened the box and looked inside. To her surprise, she found nothing in the box. She tried hard to close it, but she (7) That evening the old man came home and found the box was (8) . He was very (9) and asked the woman and her husband to leave his home."But there was nothing in the box," the woman said. "We haven’t taken anything at all. "The old man (10) them, "The box is not important, but I cannot believe you. That’s important!

第（8）空应选择（）

A．lost

B．open

C．empty

D．broken
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