A:碳酸钠溶液
B:醋酸钾固体
C:硫酸钾固体
D:硝酸钠溶液
下列更容易发生地震的一组国家是( )
⑴What's your favourite food ?____ A. Ten yuan.
⑵Where do tigers live ?____ B. They live in the forest.
⑶What's for lunch ? ____ C. I like some noodles.
⑷How much is it ?____ D. My favourite food is rice.
⑸Can you swim ?____ E. No, I can't.
下列有关人体运动的说法,正确的是( )
序号
支持面
木块对支持面的压力/N
滑动摩擦力/N
①
木板
6
3.4
②
毛巾
10
7.4
③
(a)
(b)
5.4