A:S2闭合,S1、S3断开
B:S3闭合,Sl、S2断开
C:Sl、S2闭合,S3断开
D:S2、S3闭合,Sl断开
下图所示电路图中,能用电压表正确测出灯L1两端电压的是( )
you become a professional soccer player, you will have a happy life.
月份
1
2
3
4
5
6
销售量x(万件)
10
11
13
12
8
利润y(万元)
22
25
29
26
16