A:﹣4
B:﹣1
C:5
D:13
- How much are they?
- Six yuan, please.
关于经线和纬线的叙述正确的是( )
已知△ABC中,a,b,c分别为角A,B,C的对应边,A=30°,B=45°,a=7,则边长b为( )