the answer is -$97 for sure.
9 u& |0 p1 J% b% m. P6 ^0 Uos.tvboxnow.comThink about it this way
2 f6 U4 _) B9 i# I3 T* _1 V% vTVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)公仔箱論壇$ t" @% a2 S/ ?2 N1 {
2) Now, the owner discovered that the 100 bucks is fake. You can think this as a lost of $100. therefore the overall gain is $3-$100 = -$97 |