下列哪个等级的钢结构焊缝可用于动载() ["一级焊缝","二级焊缝","三级焊缝","四级焊缝"]
哪些人在斋月可暂不封斋?() ["重病人","老人","旅行者","分娩者"]
理想动产担保交易制度的基本支柱包括()。 ["宽泛的担保财产范围","明确的优先权规则","集中统一的登记系统","便捷、高效的执行程序"]
码头及趸船非作业面应设置防护栏,护栏高度不得低于()米。 ["0.9","1.0","1.2","1.5"]
简述工作设计的目的和意义。
天安门前的石狮子,雌狮是什么形象?象征意义是什么?