以下各种化学肥料中，肥效最高，即含氮量最高的是（）

一天深夜，一场突如其来的特大泥石流吞没了小山村。次日，当救援人员循着哭声刨开泥土，掀开屋顶，发现一个光着身子蜷缩在屋梁下的两三岁小女孩竟然活着。救援人员赶紧将小女孩抱出来，可她死活不肯离开，边用小手指着边哭喊起来：”妈一一!”救援人员沿着隐约露出的一双泥手小心翼翼地往下刨，眼前现出一幅惊心动魄的画面：一个半身裸露的女人，呈站立姿势，双臂高高举过头顶，仿佛一尊举重运动员的雕塑……女人竟是一个盲人，身体早已僵硬。而她的身下，又刨出一个昂首挺立的男人!女人正是站在男人的肩上，双手高举小女孩，小女孩才奇迹般地成为这场泥石流中唯一的幸存者!

    My name is Dennis. I'm a worker(工人) of a big store. I don't work in the morning. I work at night. Every morning I come home at about 6:30. I have breakfast at 7:00. After breakfast I go to bed. I get up at around 2:30. I have lunch at 2:45 and dinner at 7:40. Then I go to work at 8:30. My work starts at 9:00. I look after(照看) the store every night. I like my work very much.