如图所示，轮O₁、O₃固定在同一轮轴上，轮O₁、O₂用皮带连接且不打滑，在O₁、O₂、O₃三个轮的边缘各取一点A、B、C，已知三个轮的半径比r₁：r₂：r₃=2：1：1，当转轴匀速转动时，下列说法中正确的是（   ）

如图是甲、乙、丙三种物质的溶解度曲线．

（1）现有接近饱和的丙物质溶液，使其变成饱和溶液的方法有：①加入丙物质；②恒温蒸发溶剂；③____ ．

（2）t₂℃时，甲乙丙三种物质溶解度由小到大的顺序是____ ．

（3）盐碱湖当地的居民，有“冬天捞碱，夏天晒盐”的结晶方法，冬天捞到的“碱”，其溶解度曲线与图中的____ 相似．

（4）在t₁℃时，将15g甲物质放入50g水中，充分溶解所得溶液质量____ 　g．

（5）t₁℃时，将甲乙丙三种物质的饱和溶液升温至t₂℃，所得溶液中溶质的质量分数由大到小的顺序是____ ．

增加：在缺词处增加一个漏字符号（^）并在其下面写出该加的词

删除：把多余的词用斜线（\）划掉。

修改：在错的词下划一横线，并在改词下面写出修改后的词。

注意：1. 每处错误及其修改均仅限一词。2. 只允许修改10处，多者（从第11处起）不计分。

    I couldn’t believe my ears when I heard my name calling. I was chosen to play the leading role in a play, that was my dream. As a shy and thin girl, I used to being quite afraid of speaking in the public. But my parents and teachers always encouraged me to do so. What they said had a deep influence of me. By now I changed greatly. In class, I am often the first one to stand up and answer questions even if I may take some mistakes. Now I am delightful that I’m brave enough to overcome the difficulty in my heart. My experience shows that we should not be afraid of losing face but only in this way can we make progresses.

— Is the baseball on the sofa?

— No, it's _________ the sofa.