*$_Two waves of the same frequency have opposite phase when the phase angle between them is?

*$_Two waves of the same frequency have opposite phase when the phase

1.	*$_Two waves of the same frequency have opposite phase when the phase angle between them is?
A.	360¬¨‚àû
B.	180¬¨‚àû
C.	90¬¨‚àû
D.	0¬¨‚àû
Answer» C. 90¬¨‚àû