the answer is -$97 for sure. tvb now,tvbnow,bttvb z" O1 h* P$ f9 P- N& C1 t
Think about it this way
4 K$ U3 m$ [% U& {' f" g; f3 GTVBNOW 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)
3 v* y* Y9 P L5 }tvb now,tvbnow,bttvb2) 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 |