某些化学试剂可用于净水，水处理中使用的1种净水剂的有效成分可表示为Al₂（OH）_nCl_m，其中m等于（　　）

大米在人体内会发生各种变化，请分析回答问题：

    My name is Maggie.I am a 13-year-old Canadian girl. I live in Toronto. It's a very big city. I can speak English and French. I have classes from 8:00 a.m. to 2:40 p.m. I have lunch at school. Many girls love playing volleyball after school, but I like swimming. I have a big family, my father, my mother and two brothers. I think China is a great country. I want a Chinese pen pal.

    Please sendemails to me if you want to be my pen pal. My email address is maggie13@yahoo.com.

“富士山、樱花、和服、相扑…”等词汇，让我们联想到的国家是（　　）