学校有540人表演团体操，每18人站成一行，一共站了多少行．

野炊时，人们常将木材架空起来燃烧，其目的是（   ）

—I hurt my arm.  
—________

阅读理解A
    I'm Linda．I can't find my keys．I lost them this morning．There is a Lost and Found box in our classroom．My keys may (可能)be in the box．
    Oh, there are many things in the box．This is a pencil box．What color is it? It's yellow．That is a white eraser．And what's that? It is a watch．A picture of a CD is on it．It's Sara's．Wow! I find my keys．One is to my classroom，and the other (另一个)is to my house．That green cup is Jack's．This baseball is his，too．I will(将)ask him to take his things．Three rulers, two pencils and two nice pens are also in the box．Whose are they? I don't know．
根据材料内容判断正误。

两根长分别是60、36厘米的绳子截成相同的小段，不许剩余，每段最多长____厘米．