In the country of Veltria, the past two years' broad economic recession has included a business downturn in the clothing trade, where sales are down by about 7 percent as compared to two years ago. Clothing wholesalers have found, however, that the proportion of credit extended to retailers that was paid off on time fell sharply in the first year of the recession but returned to its prerecession level in the second year. Which of the following, if true, most helps to explain the change between the first and the second year of the recession in the proportion of credit not paid off on time? (A) The total amount of credit extended to retailers by clothing wholesalers increased between the first year of the recession and the second year. (B) Between the first and second years of the recession, clothing retailers in Veltria saw many of their costs, rent and utilities in particular, increase. (C) Of the considerable number of clothing retailers in Veltria who were having financial difficulties before the start of the recession, virtually all were forced to go out of business during its first year. (D) Clothing retailers in Veltria attempted to stimulate sales in the second year of the recession by discounting merchandise. (E) Relatively recession-proof segments of the clothing trade, such as work clothes, did not suffer any decrease in sales during the first year of the recession. 这道题错选了A。 思路如下： 题目问的是为什么在经济不好，衣服卖不动的情况下，第一年零售商还不上钱第二年就能还上了。讲的是零售商还钱的问题。 当时留下的是A,C,D 排除D是因为觉得，即使刺激销售量衣服打折也不能说明能还上钱。可能打折卖1块，纵使家当全卖了也不够。 排除C是因为觉得， 那些本身经济状况就很差的在第一年被淘汰掉以后，剩下的那些没说经济状况如何啊，如果也不咋地，第二年还是得淘汰啊。 A选项当时觉得，即使credit extended，对pay off on time也无太大用处，但最起码跟原文意思接近。所以选了A。

25）有三个stack用来放7个file，7个file中有2个是3m高；有2个是5m高；还有3个是4m高，那么这三个stack中最高的一个stack的最小高度是多少？ 10 题目不太懂 求may老师

求may老师解答

求may老师解答

求may老师

求may老师

老师为什么9k加8可以变成9k加3咧？还有前面（1）那个列出来的式子不是应该3k加1再加1乘以y吗？

老师这道题126除以21是为了干嘛的？拆分最小公倍数嘛？那拆分的形式里面也没有6啊？还有后面的63是哪里来的？是拆分的那个最小公倍数嘛？ 如果在考试中我不能很快速的算出来类似126这样的大数的最小公倍数怎么办？有什么快速算出来的办法吗？谢谢！

求may老师

已知一个五边形有4个角相等，剩余的第5个角比其他4个角小，问这4个角一样的角的度数范围？ 108-135 求may老师解答