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问题 填空题
在△ABC中，∠A=
π
3
，BC=3，AB=
6
，则∠C=______；sinB=______．
答案

由正弦定理可得，

BC
sinA
=
AB
sinC

∴sinC=

ABsinA
BC
=
6
×
3
2
3
=
2
2

∵BC＞AB

∴

1
3
π=A＞C

∴C=

π
4

∴sinB=sin（A+C）=sinAcosC+sinCcosA

=

3
2
×
2
2
+
2
2
×
1
2
=
2
+
6
4

故答案为：

π
4
，
6
+
2
4

单项选择题

Network managers have long awaited practical voice-over-IP (VOIP) solutions. VOIP promises ease network management and decreases (66) by converging a company’s telephony and data infrastructures into one network. And a VOIP solution implemented at a company’s head-quarters with far-reaching branch offices can (67) tremendous amounts of money in long distance phone bills, provided that solution delivers POTS-like voice (68) over the Internet.
VOIP gateways are designed to convert voice from the (69) domain to the circuit switched domain. VOIP solutions use a digital signal processor (DSP) to process the voice data, preparing the voice sample for transmission by compressing voice and removing jitter. The VOIP equipment must comply with the (70) H.323 standard defined by the International Telecommunication Union, or ITU.

A．framing

B．message

C．circuit

D．packet
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单项选择题 A3型题

男性，25岁，2天前不明原因地出现干咳、胸闷，继之气喘，静滴氨茶碱无效。近3年来，秋季常出现发作性咳嗽、气短。体检：端坐呼吸，发绀，双肺呼吸音降低，有散在哮鸣音，心界不大，无杂音，脉搏120次/min，有奇脉。

若该病人突起胸痛，显著呼吸困难紫绀烦躁不安，一侧胸部饱满膨隆，呼吸运动消失，语颤消失，叩诊呈鼓音，听诊呼吸音明显减弱或消失则表明该病人可能并发了（）

A.气胸

B.纵隔气肿

C.肺不张

D.感染

E.肺心病
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