题目

如图，比例规是一种画图工具，它由长度相等的两脚AC和BD交叉构成．利用它可以把线段按一定的比例伸长或缩短.如果把比例规的两脚合上，使螺丝钉固定在刻度3的地方（即同时使OA=3OC，OB=3OD），然后张开两脚，使A，B两个尖端分别在线段a的两个端点上，当CD=1.8cm时，AB的长为（ ）A. 7.2cm B. 5.4cm C. 3.6cm D. 0.6cmDo you often think of your parents? You may say, “Of course, I  【小题1】. I buy a gift for my mother on Mother’s Day and on Father’s Day I give my father a gift,     .” But what about the other days of the year? I have a friend. She  【小题2】 in Shanghai and her parents live in another city. One day I went to see her. We talked with each other happily. Then she wanted to 【小题3】 her parents. So she dialed（拨号）the number, but then she put down the phone. After about fifteen 【小题4】, dialed the number again. “Hi, Mom…” Later I asked, “【小题5】  did you dial the number twice?” She said, “My parents are old and slow(慢) . They  【小题6】  get to the telephone quickly. I always do so when I call them  【小题7】 I want to give them enough time to answer the call.” My friend is a  【小题8】 girl. She is always thinking about her parents. You also want to be a good child, right? Please always remember 【小题9】  think of your parents, not just on some important days.