植物茎运输有机养分的管道是（） ["筛管","导管","伴胞","乳汁管"]
在PowerPoint 2003中，对幻灯片进行幻灯片切换效果的操作应该在菜单的（）栏中进行。 ["幻灯片放映","文件","插入","视图"]
在炸药和起爆器材进入爆区之前，距边孔同水平30米内撤出一切与装药无关的设备。
俄国批判现实主义文学的奠基人，俄国文学史之始祖，伟大的俄国人民诗人是（）。 ["普希金","莱蒙托夫","茹科夫斯基","雷列耶夫"]
When a hydraulic vane pump is working, which of the following is in contact with the vanes?（） (1) the rotor (2) the internal surface of the housing (3) the external surface of the housing ["(1) only","(2) only","(1) and (2)","(1), (2) and (3)"]
简述日本新鱼蚤病的症状合病理变化。
