作为给水水源,地下水水质具有哪些特点?
参考答案:
地下水水质、水温较稳定。地下水硬度高于地表水,地下水中的铁常与锰共存,超过饮用水标准,需经处理方可使用,含盐量各硬度较高。
在文中空白处填上合适的单词,补全对话。
Zhao Jing: Good afternoon.
Jack Smith: (1)______ (2)______.
Zhao Jing: (3)______ me, are (4)______ Jack Smith?
Jack Smith: (5)______, I am. (6)______ is your name?
Zhao Jing: My name is Zhao Jing.
Jack Smith: Where are you (7) ______?
Zhao Jing: (8)______ from Qingdao.
Jack Smith: (9) ______ is Qingdao?
Zhao Jing: Oh, it is in Shandong, China.
Jack Smith: (10)______ to America!
Zhao Jing: Thanks.
1.______ 2.______ 3.______ 4.______ 5.______
6.______ 7.______ 8.______ 9.______ 10.______
A.电流表的示数为3/11 A
B.通过灯泡的电流的频率为50Hz
C.电流表的示数为3/22 A
D.理想变压器原、副线圈匝数之比为2:1