题目

 In the opinion of Li Ming, a science student in that high school, physics is_______ chemistry, but much easier than English. A. as difficult a subject as                  B. as a difficult subject as C. a subject so difficult as                  D. difficult as a subject as 答案：A弹簧的长度与所挂物体的质量关系为一次函数，由图可知，不挂物体时，弹簧的长度为（　　） A、7cmB、8cmC、9cmD、10cm