You can ____your friends ____ and have a party.

小明同学用一个弹簧测力计、一个金属块、两个相同的烧杯（分别装有一定量的水和煤油），对浸在液体中的物体所受的浮力进行了研究，下图表示探究过程及有关数据．

（1）分析图B、C、D，说明浮力大小跟____ 有关．

（2）分析图____ ，说明浮力大小跟液体密度有关．

（3）物体完全浸没在煤油中所受的浮力是____ N．

（4）小明还想探究浮力大小与物体形状是否有关，他找来一小团橡皮泥、烧杯和水进行实验，实验步骤如下：

步骤一：将橡皮泥团放入盛有适量水的烧杯中，橡皮泥团下沉至杯底．

步骤二：将橡皮泥团捏成“碗状”再放入水中，它漂浮在水面上．

（a）小明通过分析得出结论：由于第一次橡皮泥团受到的浮力小于第二次呈“碗状”时受到的浮力，所以物体受到的浮力与其形状有关．

（b）同组的小红不同意小明得出的结论，她指出小明的实验有一处错误，所以才会得出错误的结论，错误的原因是：他只关注了橡皮泥形状的改变，没有控制物体都要____ ．

根据短文理解，回答问题

    Many students in the USA always take the school bus to school every day. Parents think taking the school bus is very safe. But sometimes it is also dangerous (危险的). Some students die (死亡) because they don't follow the school bus rules. Here are some school bus rules:

◆Arrive at the bus station early.

◆Wait for the bus at the bus station.

◆Don't play around (在周围) the bus.

◆Don't run everywhere at the bus station.

◆Don't walk or run in the bus when it is going.

◆Don't try to leave the bus before it stops.

These rules are good for students. Remember them and follow them. So you can keep yourself safe.