Which three are valid on line 12?() ["final","static","native","public","private","abstract","protected"]
断层面与水平面的交线称为()。 ["走向线","断层线","断距","水平线"]
1211手提式灭火器室外使用时应选择()方向站立喷射。 ["上风方向","下风方向","正对方向","背对方向"]
以沥青混凝土、钢筋混凝土或其他人工材料为防渗体的坝称为()。 ["A、均质坝 ","B、土质防渗体坝 ","C、非土料防渗体坝 ","D、黏土心墙坝"]
水利部印发了《水利工程建设领域突出问题专项治理工作方案》,其主要任务不包括() ["进一步加强水利基础设施建设","进一步规范招标投标活动","进一步加强监督管理","进一步深化体制机制制度改革"]
电子显微镜使用的电子源有两类: