安全评价亦称为()，它既需要安全评价理论的支撑，又需要理论与实际经验的结合，两者缺一不可。
A. 安全评估
B. 风险评价
C. 风险辨识
D. 危险辨识
屈服点在()Mpa以上的低合金结构钢焊接时，一般需要预热。
A. 390
B. 420
C. 460
D. 490
道德同法律、政治等社会意识形态一样属于行为规范方式，主要依靠社会舆论、传统习俗和个人内心信念等非强制力倡导和规范人们的（）
A. 思想
B. 行为
C. 作风
D. 生活方式
Which of the following is a weakness of the design of Study2？
A. Some plants were not present at each site.
B. Some seeds were not present at each site.
C. The seeds may have been removed from the dishes by animals other than ants.
D. The plants may have been eaten by animals other than ants.
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