下列物质的用途主要由物理性质决定的是（  ）

由于城市人口集中，工业发达，释放出大量废气和废热，导致城市气温高于郊区，从而引起城市和郊区之间的小型热力环流，称之为城市风．读城市风示意图，回答下题．

阅读下列短文，根据短文内容填写表格。(每空限填一词)     

    Hi! Do you know the three children? They are in a happy family. Xiao Xue is a helpful girl. She is beautiful. She likes studying. She studies very hard. She gets up early and finishes her breakfast quickly .Then she rides her bike to school . Liu Xing is a little lazy. He gets up late and then washes his face, brushes his teeth in a hurry. Then he goes to the bus stop without breakfast. He usually plays basketball after school. In the evening, he seldom (很少)does homework. He goes to bed late. Xiao Yu is a lovely boy. He gets up very slowly and then he usually takes a shower(淋浴)at home before breakfast. After that, he goes to school in his father’s car. He likes watching TV in the evening.