把餐巾纸摩擦过的塑料吸管放在支架上，吸管能在水平面自由转动，如图所示，手持带负电的橡胶棒，靠近吸管A端，A端会远离橡胶棒，实验中（　　）

​

    Halloween is a very popular holiday in North America. People celebrate it on October 31st. On this day, many people decorate their houses. Many people like to make jack-o'-lanterns. They are made from pumpkins. Some jack-o'-lanterns are funny and some are scary!

    Children wear costumes and go trick-or-treating to collect candy. Many of these costumes are scary! Witch, ghost, vampire and black cat costumes are popular.

青春期心理充满矛盾，这些内心矛盾（）

中国防灾、减灾取得了巨大成就，据此回答以下两题。