单选:()冷生和狐仙交谈后,得了什么病?A.心绞痛B.糖尿病C.头痛病D.失心疯 题目分类:文学 题目类型:单选 查看权限:VIP 题目内容: ()冷生和狐仙交谈后,得了什么病?A.心绞痛B.糖尿病C.头痛病D.失心疯 参考答案:
室外长距离管道中,当DN>500mm时,经济流速应为()。A.2~2.5m/sB.1~1.5m/sC.2~1.5m/sD.1~1.2m/s 室外长距离管道中,当DN>500mm时,经济流速应为()。A.2~2.5m/sB.1~1.5m/sC.2~1.5m/sD.1~1.2m/s 分类:文学 题型:单选 查看答案