下列代数式中，值一定是正数的是（    ）

学生应当遵守学校的规章制度。请写出你们学校5 个方面的要求，并选择其中一点或几点谈谈你的看法。

根据课文和首字母填空。
    Sandy and Sue are in a shop. They want to buy two p____ of sweets，but they are one shilling e____. That's all their p____ money. At last, they buy two small lollipops i____.
    In the afternoon, Sandy and Sue come back home from school. Tea's r____. Sandy and Sue are very h____, but Sandy's hands are very d____. Mother asks Sandy to go and w____ his hands at o____. Now Sandy's hands are clean. Look at Mum's nice clean t____! Sandy cleans his hands with it.
    On Sunday, Sue and Mum are going shopping. Mum sees a pair of nice s____, so she wants Sue to t____ them on. They are very t____ for Sue. Sue wants the pink ones and she thinks they're very p____. They're j____ right.

小信同学创作“草地上的苹果”故事的多媒体作品。他首先使用Photoshop软件制作一张背景图片，然后使用Flash软件制作动画。请回答下列问题：

1图

2图

下列不属于动物细胞工程应用的是（   ）