回複：Please take it as your homework - 回複：Wish you have read above

PJiang, I've done enought homework on it long time ago. That's why I suggest it once I saw the original post.

Personally, the answer will not help me. I am just curious about it. I also believe if you can give more explanations, maybe some people will benefit from it. As you know, people on this board, including me, always appreciate your great efforts for giving so much help.