A temporary condition of danger will not make the port（）,provided that such condition will not last an unreasonable time. ["unsafe","safe","good","bad"]
Why are removable sleeves installed on centrifugal pump shafts?（） ["They make it easier to replace the pump shaft packing","They can be economically replaced as they wear out","They can be removed when it is necessary to lighten the weight of the pump","They increase the strength of the shaft"]
在承包方队伍进入作业现场前，发包方要对其进行（）方面的教育。所有教育培训和考试完成后，办理准入手续后，凭证件出入现场。 ["消防安全","电力设施保护","社会治安方面","规程制度"]
在承包方队伍进入作业现场前，必须办理准入手续后，凭证件出入现场。证件上应有本人姓名、（）等信息。 ["本人近期免冠照片","年龄","承包方名称","准入的现场区域"]
In reference to air conditioning, when air attains the maximum amount of moisture it can hold at a specific temperature, it is said to be （）. ["superheated","saturated","condensed","convected"]
简述梁纵筋长度的计算公式。
