题目

—Let's play computer games.—__________. A . That sounds interesting B . I don't have time C . Yes, I am busy (忙碌的) D . No, I don't 答案：A2．已知等腰三角形的周长是18cm，腰长y（cm）是底边长x（cm）的函数，试求函数的关系式，并写出自变量的取值范围．