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问题 选择题

4月15 日海口市地方时上午6:30，海口市救援人员乘飞机赶往玉树灾区，5小时后到达玉树。设海口(200N，1100E)15日昼长为12小时20分，玉树(330N，970E)15日昼长为12小时50分，那么海口救援人员15日这天所经历的昼长为（    ）

A．12小时20分

B．12小时50分

C．13小时12分

D．13小时27分

答案

D   

题目分析：由两地昼长可计算出两地日出时间：海口=12-12：20/2=5:50，玉树=12-12：50/2=5：35；飞机起飞到达玉树时的时间为6：30+5+（110-97）*4=10：38；10：38以前的昼是在海口和飞机上过的共是6：30-5：50+5=5：40，10：38以后是在玉树经历的白昼时长为12：50-10：38=7：47，综合得出救援人员15日这天所经历的昼长为=7：47+5：40=13：27.。选D正确。

单项选择题

不属于中药注射剂的质量检查项目的是

A．装量

B．澄明度

C．渗透压

D．无菌

E．相对密度
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单项选择题

Typically, these are concern with the establishment of (66) the network and with the control of the flow of messages across this channel. The provision of such facilities is only part of the network requirements, however, since in many applications the communicating computers may be of different types. This means that they may use different programming languages and, more importantly, different forms of (67) interface between user(application)program, normally referred to, as application processes or APs, and the underlying communication services may be (68) For example, one computer may be a small single -user computer, while another may be a large (69) system. In the earlier days of computer communication, these issues meantthat only closed communities of computers ( that is, from the same manufacturer) could communicate with each other in a meaningful way. IBM’s Systems Network.
Architecture (SNA) and DEC’s Digital Network Architecture (DNA) are just two examples of Communication software packages produced by manufacturers to allow their systems to be int erconnected together. These proprietary packages, however, of which there am still many inexistence, do not address the problem of universal interconnect ability, or open systems interconnection. In an attempt to alleviate this problem, (70) , in the late 1970s, formulated a reference model to provide a common basis ( or the coordination of standards developments and to allow existing and evolving standards activities to beplaced into perspective with one another.

A．DNA

B．SNA

C．the OSI

D．the ISO
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