When people engage in activities that help others, their brain releases endorphins, the brain’s natural opiates, which induce in people a feeling of well-being. It has been suggested that regular release of endorphins increases people’s longevity. And a statistic on adults who regularly engage in volunteer work helping others shows that they live longer, on average, than adults who do not volunteer. However, that statistic would be what we would expect even if volunteering does not boost longevity, because___________ Which of the following most logically completes the argument? A In the communities studied, women were much more likely to do regular volunteer work than men were, and women tend to live longer than men do B The number of young adults who do regular volunteer work is on the increase C The feelings of well-being induced by endorphins can, at least for a time, mask the symptoms of various conditions and diseases, provided the symptoms are mild D It is rare for a person to keep up a regular schedule of volunteer work throughout his or her life E Some people find that keeping a commitment to do regular volunteer work becomes a source of stress in their lives 错选了C，答案给的A。A说女士比男士更可能做志愿活动，女士比男士活得长。这不是支持原文了么？可以题目不是应该驳斥吗？

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