题目

I know I should have told the headmaster at the time. That was my real   1  . He had gone out of the study for some   2  , leaving me alone. In his absence I looked to see   3   was on his desk. In the   4   was a small piece of paper on which were written the   5   “English Writing Prize 1949. History Is a Serious of Biographies (人物传记)”. A(n)   6   boy would have avoided looking at the title as soon as he saw the   7  . I did not. The subject of the English Writing Prize was kept a   8   until the start of the exam so I could not   9   read（1）某同学在用螺旋测微器测定某薄片的厚度时，读数如图所示。可知该薄片的厚度d＝______mm。（2）某同学用卡尺来测量工件的直径，读数如图所示。该工件的直径为d＝______ mm。（3）某同学用多用电表按正确步骤测量一电阻阻值，如图，则这电阻值是_   Ω。如果要用此多用电表测量一个约20Ω的电阻，为了使测量比较精确，选择开关应选的欧姆挡是_ _。