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问题 单项选择题

小明和小强参加同一次考试，如果小明答对的题目占题目总数的3／4，小强答对了27道题，他们两人都答对的题目占题目总数的2／3。那么两人都没有答对的题目共有（）。

A．3道

B．4道

C．5道

D．6道

答案

参考答案：D

解析：

设考试的题量为X，小明小强都做错的题数为Y，则根据题意可列出：X*3/4+27-X*2/3=X-Y，化简可得：Y=X*11/12 – 27。 因为X、Y都是正整数，X又肯定得是12的倍数，所以将X=12、24、36、48……代入等式，发现当X=36时，Y=6，与D项相符。但若X=48的话，则Y=17，选项中没有适合的，故本题选D。

单项选择题

How to protect children Web fans from unsuitable material on-line while encouraging them to use the Internet has long been discussed in the US.
For some parents, the Internet can seem like a jungle, filled with danger for their children. But jungles contain wonders as well as dangers and with good guides, some education, and a few precautions, the wilds of the Internet can be safely navigated. "Kids have to be on-line. If we tell our kids they can’t have access to the Internet, we’re cutting them off from their future, " said an expert.
Most kids have started to use search engines. Many of them are great for finding tons of interesting Internet sites, and they can also locate places where you might not want your kids to go. There are search engines designed just for kids. A certain software contains only sites that have been selected as safe. The most popular way to limit access would be to use what is known as a "content screener". But this can’t be wholly reliable, and the best thing parents can do is to talk to their kids and let them know what is OK or not OK to see or do on the Internet. Another way is that mum or dad is nearby when the child is surfing the Internet.
A few other tips
·Don’t put the PC in a child’s room but keep it in an area where mum or dad can keep an eye on things. That also makes the Internet more of a family activity.
·Ask your child what he or she has been doing and about any friends they make on-line.
·Tell your child not to give on-line strangers personal information, especially like address and phone number.
·And tell your children never to talk to anyone they meet on-line over the phone, send them anything, accept anything from them or agree to meet with them unless you go along.

The best way to protect children from improper material is ______.

A. to install (安装) a content screener on the computer
B. to buy some search engines for the children
C. to be nearby when they are surfing the Internet
D. to talk to the children and persuade them to tell right from wrong
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单项选择题

患儿，12岁。癫痫发病10年，屡发不止，发时瘛瘛抖动，时有眩晕，智力迟钝，腰膝酸软，神疲乏力，少气懒言，四肢不温，大便稀溏，舌淡苔白，脉沉细。其治法是

A．豁痰开窍

B．熄风止痉

C．健脾化痰

D．镇惊安神

E．补益脾肾
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