我国科举制正式诞生是在（     ）

    It was Saturday. Mike stayed at home alone(单独地). His parents went to visit his grandparents in another city. He did his homework and read books. After lunch, he watched TV and played basketball on the playground with Jack. He felt very tired. In the evening, his parents came back and brought him some presents. They were a schoolbag and a basketball. Mike felt very excited!

____

用计算器算出:18千克大米的总价是____元.

用计算器算出:9.5千克大米的总价是____元.

用计算器算出:26千克大米的总价是____元

如果点P（m，1﹣2m）在第四象限，那么m的取值范围是____