利用身边常见易得的简陋器材，同样能进行实验探究活动．现给你一把钢尺（辅助器材任选）．请你仿照示例按要求将相应内容填入表中．
— I've taken someone else's overcoat by mistake. Is it Jack's?
— It ____ be his. He seldom wears white. [ ]
A. can't
B. mustn't
C. won't
D. shouldn't
嵌镶金相试样用的是酚醛树脂类的热固性塑料。若酚醛塑料的密度为1.4g/cm3，试求在10cm3的圆柱形试样中所含的分子质量为多少
