A:Spotting shopping
B:Spotted shopping
C:Having spotted to sho
D:Spotted to sho
在△ABC中,角A、B、C所对的边分别为a、b、c,若b2+c2-a2=3bc,且b=3a,则下列关系一定不成立的是( )
It's raining. I need a ____(雨衣).