在安排储存场所时，应将一些既怕热、又怕冻，且需要较大湿度的物品，存放在温度较低的阴凉场所。
参考答案：错
设NA为阿伏加德罗常数的数值。下列说法错误的是
A．20g重水（D2O）中含有10NA个电子
B．标准状况下，22.4L一氯甲烷的分子数约为NA
C．4.6 g Na在氧气中完全反应生成Na2O和Na2O2，转移电子数为0.2NA
D．25℃时，1L pH = 14的Ba(OH)2溶液中，Ba2+ 数为NA
Given the following information about a firm: Net Sales = $1000 Cost of Goods Sold = $ 600 Operating Expenses = $ 200 Interest Expenses = $ 50 Tax Rate = 34% What are the gross and operating profit margins Gross Operating Margin Operating Profit Margin（）①A. 2O% 15% ②B. 4O% 10% ③C. 40% 20%
A. ①
B. ②
C. ③
