题目

He can see his parents in the        .     A. ruler         B. picture     C. pen        D. number 答案：B|x-a|＜ε,|y-a|＜ε,则下列不等式一定成立的是(    )A.|x-y|＜ε          B.|x-y|＞2ε         C.|x-y|＞ε           D.|x-y|＜2ε