由大量出血所导致的病理变化是 A．气滞 B．气逆 C．气陷 D．气闭 E．气脱

(6分)光纤通信是70年代以后发展起来的新兴技术，世界上许多国家都在积极研究和发展这种技术．发射导弹时，可在导弹后面连一根细如蛛丝的光纤，就像放风筝一样，这种纤细的光纤在导弹和发射装置之间，起着双向传输信号的作用．光纤制导的下行光信号是镓铝砷激光器发出的在纤芯中波长为0.85的单色光．上行光信号是铟镓砷磷发光二极管发射的在纤芯中波长为1.06的单色光．这样操纵系统通过这根光纤向导弹发出控制指令，导弹就如同长“眼睛”一样盯住目标．根据以上信息，回答下列问题：

①在光纤制导中，上行光信号在真空中波长是多少？

②为什么上行光信号和下行光信号要采用两种不同频率的光？(已知光纤纤芯的折射率为1.47)

阅读理解

    Riding School:

   You can start horse-riding at any age. Choose private or group lessons any weekday between 9 a.m.

and 8:30 p.m. (3:30p.m. on Saturday). There are 10 kilometers of tracks and paths for leisurely rides

across farmland and open country. You will need a riding hat.

   Opening Hours: Monday through Friday: 9:00a.m.---8:30 p.m.

   Phone: (412) 396---6754 Fax: (412)396---6752

Sailing Club:

    Our Young Sailor's Course leads to the Stage 1 Sailing qualification．You'll learn how to sail safely

and the course also covers sailing theory and first aid．Have fun with other course member , afterwards

in the clubroom．There are 10 weekly two-hour 1essons (Tuesdays 6 p．m．～8 Pp．m．)．    

    Opening Hours:Tuesdays:6:00 p．m．-8:00 p．m．

    Phone:(412)396-6644 Fax:(412)396-6644

Diving Centre:

    Our experienced instructors offer one-month courses in deep-sea diving for beginners．There are two

evening lessons a week,in which you learn to breathe underwater and use the equipment safely．You

only need your own swimming costume and towel．Reduced rates for couples．

    Opening Hours:Monday and Friday:6:30 p．m．-8:30 p．m．

Phone:(412)396-6312  Fax:(412)396-6706

Medical Center:

    The staff of the Medical Center aim to provide convenient and comprehensive medical care to

students and staff of the university．The center is well equipped and the staff here are trained to deal

with a broad range of medical problems．Both female and male doctors as well as nursing staff are

available for consultation．Also,all kinds of medicines are sold here and are cheaper for students than

other drugstores．

    Opening Hours:24 hour from Monday to Sunday

Phone:(412)396--6649  Fax:(412)396-6648

Watersports Club:

   We are a two-kilometer length of river for speedboat racing, and water-skiing, A beginners' course

consists of ten 20-minute lessons. You will learn to handle boats safely and confidently, but must be

able to swim. The club is in a convenient central position and is open daily from 9a.m. to 4 p.m. with

lessons all through the day.

   Opening Hours: Monday through Friday: 9:00a.m. ---4:00 p.m.

   Phone: (412)396---6899  Fax: (412)396---6890      

1. If you want to swim and enjoy activities which are fast and a bit dangerous,you should join     ．

A. Watersports Club  

B. Diving Centre    

C. Sailing Club    

D. Riding School

2. If you want to experience a new activity in the countryside in the mornings,you may fax        ．

A. (412)396-6648  

B. (412)396-6706  

C. (412)396-6752  

D. (412)396-6876

3. If you are planning to explore the ocean depths,you should attend your lessons at      .

A. 24 hour from Monday to Sunday    

B. Monday through Friday:7:00 a．m．-10:00 p．m．

C. Tuesdays:6:00 p．m．-8:00 p．m．

D. Monday and Friday:6:30 p．m．-8:30 p．m．

4. Which is NOT the convenience that the Medical Center provides?

A. Good equipment．                  

B. Well trained staff members．

C. Various less expensive medicines．    

D. Nursery for newly-born babies

临床上出现“长吸气式呼吸”，可能损害部位在（）

A.脑桥上部

B.大脑皮质系统

C.脑桥下部

D.中脑被盖部

E.延髓

电控燃油系统空气供给系统中，检测进气压力的是（）。

A.怠速旁通阀

B.进气压力传感器

C.空气滤清器

D.进气管

由于（），一氧化碳传感器应布置在巷道的上方。

A．一氧化碳的密度大于空气

B．一氧化碳的密度小于甲烷

C．一氧化碳的密度小于空气

D．一氧化碳的密度大于甲烷