下面关于珠江三角洲外向型经济的描述，不正确的是（　　）

    Mr. Brown works on a farm. Mr. Green works in a park. But they don't know each other. Today is Sunday. Mr. Brown comes to the park. He feels tired. He wants to have a little rest. He sees a red chair under a tree over there. So he walks to the chair. Mr. Green is behind him. Mr. Green runs to the chair with a board when he sees Mr. Brown come to the chair. But Mr. Brown runs faster（更快） than Mr. Green. Then he sits on the chair. Mr. Brown is very happy. But Mr. Green doesn't say anything. He gives the board（板子） in his hand to Mr. Brown. It says, "Wet Paint(油漆未干). "

如图所示，某课外兴趣小组做水果电池实验中，发光二极管可以发光．已知发光二极管的左边引脚是正极，则这个水果电池中，铜片相当于电源的 ____极，锌片相当于电源的 ____极，在这个水果电池的外部，电子从 ____片流向 ____片（选填“铜”或“锌”）．