《工业金属管道工程施工及验收规范》规定，管道安全阀应按设计文件规定的开启压力进行试调。调压时压力应稳定，每个安全阀启闭试验不得少于()次。
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What is Edgar Allen Poe by profession according to the passage？
A. He is a cosmologist.
B. He is a cosmogonist.
C. He is a university instructor.
D. He is a famous poet.
Which of the following is the main idea of this passage？
A. The crew life at the ISS should be made more enjoyable.
B. More crew members at the ISS mean more disasters.
C. The Soyuz capsules can only expire to the year 2006.
D. The ISS is in need of more crew members.
有关风管系统施工对板材拼接要求的叙述，错误的是()。
A. 镀锌钢板及含有保护层的钢板的拼接，应采用咬接或铆接，且不得有十字形拼接缝
B. 塑钢板的涂塑面应设在风管内侧，加工时应避免损坏涂塑层，损坏部分应及时修补
C. 铝板风管板材厚度大于1.5mm时，板材拼接可采用咬接，但不应采用按扣式咬口
D. 不锈钢板厚度小于或等于1mm时，板材拼接可采用咬接
Most cosmogonists believe that ______.
A. the Sun's equator lies in the planetary plane
B. the Sun leans over because of loss of mass
C. the Sun and the planets have different origins
D. the Sun took shape somewhere in the Galaxy
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