有微量放射性的钨极是（） ["纯钨级","钍钨极","铈钨极","铜钨极"]
以下关于闭合多条路径的操作正确的是（） ["按住 SHIFT 键，然后使用挑选工具乱序选择对象与框选对象使用任何闭合路径操作结果都一样 ","按住 SHIFT 键，然后使用挑选工具乱序选择对象与框选对象使用闭合路径中“最近的节点和直线”命令结果是一样的 ","按住 SHIFT 键，然后使用挑选工具乱序选择对象与框选对象使用闭合路径中“从起点到终点使用直线” 命令结果是一样的 ","按住 SHIFT 键，然后使用挑选工具乱序选择对象与框选对象使用闭合路径中“从起点到终点使用曲线” 命令结果是一样的"]
During a recent OSPF election among three routers, RTA was elected the DR and RTB was elected the BDR, as seen in the graphic. Assume that RTA fails, and that RTB takes the place of the DR whi le RTC becomes the new BDR. What will happen when RTA comes back online？（） [" A new election will take place establishing an all new DR and BDR based on configured priority levels and MAC addresses."," RTA will take the place of DR immediately upon esta blishing its adjacencies."," RTA will take the place of DR only if RTB fails."," RTA will take the place of DR only if both RTB and RTC fail."]
《中国共产党纪律处分条例》规定，直接经济损失，是指与违纪行为有直接或间接因果关系而造成财产损毁的实际价值。
下列选项中属于流动资产的有（）。 ["货币资金","短期投资","应收及预付款项","存货"]
从研究的层次上看生态工程与环境工程的研究水平是（）水平，而生物工程是（）水平。
