我国电力系统中性点接地方式有三种，分别是（）A、直接接地方式 B、经消弧线圈接地方式C

There is a saying, “An apple a day keeps the doctor away.” Although eating properly is important, being kind to others is also good tor your health. Studies show that people who perform kind acts are more relaxed, happier, and healthier than other people.

In one study at Arizona State University researchers, found that many volunteers experienced a sudden feeling of joy, followed by a long period of calm, after performing a kind act.  This feeling, called “a help’s high” may actually help reduce stress (压力) as the body releases (释放) naturally painkillers.

Stress can cause’ serious health problems, and heart depression, and .sleeping problems. However, the study found that volunteers had fewer *stress-related health problems when they did helpful things for other people.

The study also found that people who did nice things for others felt better about themselves as well. They had higher self-esteem (自尊), and were’ happier. Many believe this is because volunteers spend more of their time with other people. People who are more outgoing are often healthier.

Another study at the University of Michigan’s Survey Research Center confirmed the health benefits of volunteering. A ten-year study showed that people who volunteered live longer than those who didn’t. Although you shouldn’t need a reason to be helpful, it is nice to know that kindness may help you live longer.

小题1:The reading is mainly about ＿＿＿＿＿＿.

A．healthy people are kind because they have more energy

B．one has to eat an apple every day to become healthy

C．kind people can be stressed because they are always helping

D．doing kind things can make you feel good and help you he healthier小题2:According to the reading ＿＿＿＿＿＿.

A．it is better to be kind than to eat well

B．kindness can help you feel healthy

C．an apple a day can keep doctors away

D．eating correctly makes one happy and healthy小题3:You can get a help’s high ＿＿＿＿＿＿.

A．by volunteering your time

B．by taking painkillers

C．by eating properly

D．by sleeping well小题4:The study found that people who help others can have ＿＿＿＿＿＿.

A．sleeping problems and stress

B．less natural painkillers

C．overeating and depression problems

D．fewer health problems小题5:Another study of almost 3 ,000 men showed that people who volunteered ＿＿＿＿＿.

A．lived longer

B．needed a reason to be helpful

C．wanted to live longer

D．had lower self-esteem

6个月的小儿，腹泻3天，每天8次，眼眶明显凹陷，尿量明显减少，其脱水程度为（）

A.极轻度脱水

B.轻度脱水

C.中度脱水

D.重度脱水

E.极重度脱水

肺癌病人中有吸烟史的占()

A.70%~80% 

B.10%~20% 

C.90%以上 

D.50%~60% 

E.40%~50%

已知：Mg+CuO═Cu+MgO，现将一定量镁和氧化铜的粉末充分加热后，将剩余固体加入足量的稀硫酸中．下列现象与结论不正确的是（　　）

A．若有气泡产生，固体剩余物中一定含有镁粉，一定不含铜粉

B．若溶液变为蓝色，固体剩余物中一定含有CuO

C．固体剩余物不一定能全部溶解到稀硫酸中

D．在稀硫酸中一定发生的反应是MgO+H₂SO₄=MgSO₄+H₂O

泌尿系统的功能是产生尿液，排出机体内溶于水的代谢产物。（ ）