建设工程信息管理系统的目标是（）。 A.完善信息管理 B.提供智力支持 C.实现信息 发布时间：2017-05-06 18:48 │ 来源：www.tikuol.com 题型：多项选择题 问题： 建设工程信息管理系统的目标是（）。A.完善信息管理B.提供智力支持C.实现信息的系统管理D.形成完善体系E.供必要的决策支持
题型：多项选择题 A Simple Scientific ExperimentBelow is a description of a single scientific experiment. It shows us how iron reacts ( 反应) with air and with water.Aim : To find out if iron rusts( 生锈) (a) in dry air ; (b) in water that has no air in it ( air- free water) ; (c) in ordinary water.Materials : 3 clean iron nails ( 铁钉) ; test tubes ; test tube holder ; cotton wool ; oil ; Bunsen burner.Iron in dry airMethod(1)Put some iron nails at the bottom of a test tube.(2)Push some cotton wool down the tube.(3)Leave the tube for one week.ResultAfter one week, the nails have not rusted.ConclusionIron does not rust in dry air.Iron in air-free water Method(1)Half-fill a test tube with water.(2)Boil the water for three minutes. (This makes sure there is no air in the water.(3)Put two or three clean nails in the water.(4)Add some oil to the water. (This will keep air out of the water.)(5) Leave the tube for one week.Result The nails do not rust in the tube with air-free water.ConclusionIron does not rust in air- free water.Iron in ordinary waterMethod (1)Half –fill a test tube with water and add two or three clean nails.(2)Leave the tube for one week.ResultThe nails rust in the tube with ordinary water.ConclusionIron rusts in ordinary water. (238 words)小题1:In the first part of the experiment the cotton wool is most probably used to ______________.A．keep the air dryB．keep the tube wetC．make the nails rustD．keep the tube clean小题2:What are necessary steps to make sure the water in the tube is air free?①Leave half a tube of water in it ②Boil the water for some time③Put some clean iron nails in the tube ④Add some oil to the waterA．①②B．①③C．②③D．②④小题3:We can conclude from the experiment that only ____________ makes iron rusty.A．dry airB．cotton woolC．ordinary waterD．air-free water 查看答案
题型：多项选择题 现有甲、乙、丙、丁、戊五种离子化合物形成的溶液，分别由K+、NH4+、Ag+、Ba2+、Fe3+、Cl-、OH-、CO32-、SO42-、NO3-中的阳离子和阴离子各一种组成（五种离子化合物所含阴、阳离子各不相同）．已知：①室温时，0.1mol•L-1乙溶液的pH=10，②丙、丁、戊三种溶液的pH均小于7，③丙溶液分别与其他四种溶液反应均生成沉淀，④甲溶液与丁溶液在加热条件下反应既产生白色沉淀又产生刺激性气味的气体，生成的白色沉淀不溶于稀硝酸．根据以上实验事实可以推断（ ）A．甲为K2SO4溶液B．乙为K2CO3溶液C．戊为Fe（NO3）3溶液D．丁为NH4Cl溶液 查看答案
题型：多项选择题 男性，12岁。智力低下、言语障碍11年。CT检查如图所示，请根据CT图像给出正确诊断（）A.蛛网膜囊肿B.脑裂畸形C.Dandy-Wallker综合征D.囊性胶质瘤E.左侧侧脑室室间孔闭锁或狭窄 查看答案
