关于地球同步卫星,正确的是() A.周期为24h B.线速度不变 C.同步卫星质

题型:选择题

问题:

关于地球同步卫星,正确的是(  )

A.周期为24h  

B.线速度不变

C.同步卫星质量可能不相等

D.同步卫星可以定点于北京上空,且其相对于地面始终保持静止

考点:万有引力定律
题型:选择题

汉武帝采纳主父偃的建议,规定:诸侯王死后,除嫡长子继承王位外,其他子弟可分割王国的一部分土地成为列侯,由郡守统辖。这一措施即

A.设立中朝

B.酎金夺爵

C.推恩令

D.设置刺史

题型:选择题

As hand-held devices such as smartphones are becoming more common, users are reporting some new physical problems. Florida chiropractor Dean Fishman began noticing an increased number of patients talking about neck and shoulder pain. He discovered these symptoms were due to the overuse of hand-held devices, particularly the action of bending the neck, and then coined the term “Text Neck.” As if the painful symptoms weren’t bad enough, Fishman warns that an untreated case of Text Neck could lead to permanent spinal(脊椎) damage.

Other doctors have warned about “iPad Hand,” a condition that occurs when people use tablets like the iPad for hours at a time. Most people use their left hand to support the tablet and their right hand to tap or scroll. Doing this for long periods without changing positions can result in severe joint pain.

In order to avoid or reduce the possibility of getting Text Neck or iPad Hand, use the following basic ergonomic(人体工学的) principles:

Avoid awkward positioning. Don’t strain your neck, and stay aware of how you are positioned in relation to the device. Make sure that both your neck and shoulders are relaxed and that you aren’t leaning over for a long period of time.

Take frequent breaks when using any kind of mobile device. Many doctors recommend that users change their position every 15 minutes.

When using a tablet, use a case that can support the device on a table or your lap at a comfortable viewing angle.

Along with a case, use a separate keyboard with your tablet. This will be more comfortable since you’ll be resting both hands on the keyboard. And since you won’t be holding the tablet, you’ll be less likely to experience hand or arm pain.

小题1:What kind of product for hand-held devices does the writer discuss?

A.One for recording.

B.One for charging.

C.One for telephoning.

D.One for typing.小题2:Which of the following is closest in meaning to the underlined word “coined” (Para1)?

A.cashed

B.created

C.changed

D.completed小题3:Which of the following is TRUE according to the passage?

A.If you are holding an iPad for long periods, it could cause spinal damage.

B.Text Neck symptoms include long-term damage in the back.

C.You are advised to lean over in relation to the device.

D.You should rest your hands on the keyboard at times.小题4:In which magazine would you most likely find this article?

A.Personal Finance

B.Science Fiction Monthly

C.Mind and Body

D.Smartphone World

题型:选择题

采用生产能力指数法进行投资估算时正确的公式是()。

A.A

B.B

C.C

D.D

题型:选择题

照海所通的奇经八脉是()。

A.任脉

B.督脉

C.冲脉

D.带脉

E.阴跷脉

题型:选择题

癃的特点是()

A.小便不利,点滴而短少,病势较缓

B.小便量少,点滴而出甚则小便闭塞不通

C.小便频急,淋漓不尽, * * 涩痛,痛引腰腹

D.小便闭塞,点滴不通,病势较急

E.小便闭塞,吐逆便秘

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