阅读理解。

   Today is Friday. It's my birthday. I get up at 6:40. I put on my new yellow shirt and blue jeans. I like my red shoes. I eat some bread and drink milk at 7:00 for breakfast. At 7:25, I go to school. At 10:00, I go to the library. It's on the second floor. I read a story-book there. I go home at 11:30.

为了便于对生物的研究，常要对生物进行分类，下列不能作为分类依据的是（    ）

在硝酸铜、硝酸锌、硝酸亚铁混合溶液中加入铝粉，充分反应后过滤．

①若滤纸上有两种金属，则这两种金属是____（填化学式）．

②若滤液中只有一种溶质，则这种溶质是____（填化学式）．

【实验器材】____、____、____；

【实验步骤】  小彬同学设计的测量步骤如下，其中多余的是____

A.测出箱子的质量ｍ             B.测出楼梯的总长度L

C.测出一楼到三楼的竖直高度h    D.测出小云上楼所用的时间t