目前提供的固定网国际长途电话业务包括国际直拨电话和港澳台直拨电话（港澳台直拨电话比照

Information systems design is defined as those tasks that focus on the specification of a detailed computer-based solution. Typically, there are four systems design tasks for in-house development.

1) The first task is to specify (71) ,which defines the technologies to be used by one, more, or all information systems in terms of their data, processes, interfaces, and network components. This task is accomplished by analyzing the data models and process models that are initially created during requirements analys16.

2) The next systems design task is to develop the (72) . The purpose of this task is to prepare technical design specifications for a database that will be adaptable to future requirements and expansion.

3) Once the database prototype has been built, the systems designer can work closely with system users to develop input, output and dialogue specifications. The (73) must be specified to ensure that the outputs are not lost, misrouted, misused, or incomplete.

4) The fourth design task involves packaging all the specifications from the previous design tasks into a set of specifications that will guide the (74) activities during the following phases of the systems development methodology.

Finally, we should (75) and update the project plan accordingly. The key deliverable should include a detailed plan for the construction phase that should follow.

（72）处应填（）。

A．database design specifications

B．database organization decisions

C．data structure specifications

D．data distribution decisions

下列有关实验原理、装置、操作或结论的描述中，不正确的是（夹持仪器略去未画）[ ]

A.

B.

C.

D.

巨幼红细胞贫血在消化系统的主要临床表现有（）

A.舌炎

B.镜面舌

C.舌萎缩

D.杨梅舌

E.牛肉舌

2013年10月20日，也就是哈尔滨市的年度冬季燃煤取暖系统开启的第二天，以哈尔滨为中心，吉林、黑龙江、辽宁在内的东北地区发生了大规模的雾霾污染。由于东北地区普遍燃烧煤炭取暖，大量烟尘因此直接排到空中，是本次污染事件的主因。东北地区大部均被浓密的雾霾覆盖。在哈尔滨市，PM2.5的日度平均值一度达到每立方米1000毫克，超出世界卫生组织安全标准40多倍，甚至比北京还要严重。能见度降至20米，机场被迫关闭，两千多所学校停课。雾霾也导致黑龙江省境内多条高速公路被迫关闭。10月22日至23日，东北地区仍然被雾霾覆盖，PM2.5平均浓度保持在每立方米200毫克以上。挥之不去的雾霾从一定意义上警示我们，在认识世界和改造世界的活动中，既要利用自然，又要尊重自然，与自然和谐相处。

运用规律的有关知识，分析雾霾天气给我们的警示。