复数Z=3-1i（i为虚数单位）的模为（ ） A．2 B．3 C．10 D．4

如图所示，在倾角θ=37°的光滑斜面上存在一垂直斜面向上的匀强磁场区域MNPQ，磁感应强度B的大小5T，磁场宽度d=0.55m，有一边长1=0.4m，质量m₁=0.6kg，电阻R=2Ω的正方形均匀导体线框abcd通过一轻质细线跨过光滑的定滑轮与一质量m₂=0.4kg的物体相连，物体与水平面间的动摩擦因数μ=0.4，线框从图示位置自由释放，物块到定滑轮的距离足够长．（g=10m/s²）求：

（1）线框abcd还未进入磁场的运动过程中，细线拉力为多少？

（2）当ab边刚进入磁场时，线框恰好做匀速直线运动，求线框刚释放时ab边距磁场MN边界的距离x多大？

（3）cd边恰离开磁场边界PQ时，速度大小为2m/s，求运动整过程中ab边产生热量Q为多少？

Listening to music can help me focus better. Since I discovered it two years ago, I’ve used music to get through boring work or to focus creatively. I’ve found that it can make even the dullest jobs enjoyable and help clear mental blocks to creativity.

I first noticed the good effects of music while playing video games. It was a few days before Christmas in 2005 and I was playing online video games. My parents had just given me a new MP3, so I decided to listen to music through the headphones while I played. After a few minutes I noticed a great change in my style of play. I was playing more naturally. The music relaxed me, and, to a certain extent, distracted me from the game, allowing my subconscious (潜意识的) talent to come through. The music also helped me block out the outside world. With those headphones on I was like a machine, moving from one task to the next without unnecessary thoughts or actions.

Music can also have a great effect on mood. If I’m in a bad mood at work, I’ll listen to some of Bob Marley’s and get down to business. It always takes my mind off what I’m doing and makes me a happier person. The same is true for classic rock. One summer, I did a boring job collecting bottle openers by hand. Without a radio playing classic rock in the background, I would have hated life.

Listening to music with relaxing rhythms and a positive message helps you forget your work and think happy thoughts. But the results you see will depend heavily on your personal tastes. Experiment with the types of music you listen to during certain tasks. By trial and error you’ll finally discover your best choice. I’m always looking for new concentration aids, so I’d love to know what type of music works best for me.

小题1: We can infer that the passage was written in __________.

A．2005

B．2006

C．2007

D．2008小题2:The author first discovered the effects of music __________.

A．from his parents

B．by chance

C．at work

D．when he was a child小题3:Which of the following statements is NOT an effect of music for the author?

A．It helps him block out the outside world.

B．It arouses his subconscious talent.

C．It helps his mind relax.

D．It makes him work without any thought.小题4:The author mentions the experience of collecting bottle openers in Paragraph 3 to ________.

A．tell us that life is dull

B．prove that music affects mood

C．tell us how to seek happiness

D．tell us bad mood can affect work小题5:In order to get the greatest effect of music, you are advised to ________.

A．listen to some of Bob Marley’s

B．only choose relaxing music

C．test all kinds of music

D．listen to classic rock

胎龄32周早产儿，生后1周，因不能进食，靠全静脉营养，在治疗过程中出现脱水并高氮质血症。考虑原因可能为（）

A.给氨基酸过多

B.低血糖

C.高血糖

D.高氯性酸中毒

E.高脂血症

咳血方的臣药是（）

A.青黛、栀子

B.瓜蒌、海粉

C.当归、川芎

D.柴胡、大黄

E.桃仁、红花

国标《复合塑料编织袋》规定，（）型编织袋允许的装载质量为21~30Kg。

A.TA

B.A

C.B

D.C