为了了解全校学生的视力情况,小明、小华、小李三个同学分别设计了三个方案.
①小明:检查全班每个同学的视力,以此推算出全校学生的视力情况.
②小华:在校医室找到2000年全校的体检表,由此了解全校学生视力情况.
③小李:抽取全校学号为5的倍数的同学,检查视力,从而估计全校学生视力情况.
以上的调查方案最合适的是____ (填写序号).
A dog has a piece(片) of meat in his mouth. He sees himself(他自己) in the water. He thinks it is another dog. That dog has a piece of meat in his mouth,too. He wants to get(得到) his meat. Then he can have two pieces. He opens his mouth to bark(吠叫) and his meat goes down into(在……里面) the water.
32×68=____
17805-3976=____