人的生命如洪水奔腾，不遇岛屿和暗礁，难以激起美丽的浪花。从中我们可以悟到（    ）

①挫折可以提高生命的韧性                         ②挫折可以增强生命的抗挫性

③挫折可以促成生命实现更高远的目标     ④只要是挫折，都能增加生命的意义

读短文，按要求完成下列各题题。第1题为判断正误；第2、3 题为回答问题；第4题在空白处填入一个单词；第5题为对划线部分英译汉。

    I'm Leo. There is an artist in my family. She is Lisa. Lisa likes drawing a lot. Here are her three drawings (图画).

    There is an animal in the first drawing. It has two big eyes, a big mouth and two small ears. It has long arms and long legs. It is black and white. There are some apples in its hands. It looks very happy. What is it? I don't know, but Lisa says it is a panda.

    There is a woman in the second drawing. She is thin. She has straight blonde hair, a small mouth, a big nose and two big eyes. She looks angry (生气的). Who is she? Lisa says she is our mom. But Mom has curly blonde hair, small eyes and a small nose.

    There is an animal in the third drawing, too. Its head is an apple. Its hair and tail (尾巴) are leaves (树叶). It has a long mouth, and it is a banana. Its four legs are carrots. What is it? Lisa says it i s a horse (马), but it doesn't look like a horse.

    Lisa is really a great artist, isn't she?

当k＞0时，正比例函数y=kx的图象大致是（　　）

⑴将少量白色粉末放入足量水中，搅拌、静置、过滤，得到白色固体和滤液；

⑵向所得固体中加入稀硝酸，固体溶解并有气体放出；

⑶向所得滤液中加入稀硫酸，有白色沉淀生成。

试推断：该粉末一定含有____，一定不含有____。写出步骤（2）涉及到的化学方程式 ____ 。