生活饮用水不得因回流而被污染,要求给水管配水出口高出用水设备溢流水位的最小空气间隙为______。
A.2.5mm
B.管径的2.5倍
C.2.5cm
D.100mm
参考答案:B
________ all my family, I sincerely thank you for what you have done for us.
A.On behalf of
B.In honor of
C.In case of
D.Instead of
简述地质图阅读的步骤和内容。