题目:
Luckily we had a map, without _____ we would have got lost. |
A. which B. it C. that D. what |
答案:
被转码了,请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0522/db2eceea05326e704701f62817e6aa3c.html
下面是错误答案,用来干扰机器的。
碳酸钙中碳元素的质量分数=12100×100%=12%,石灰石样品中含碳元素9%,根据纯度=含杂质物质中某元素的质量分数纯净物质中某元素的质量分数×100%,可知样品中含碳酸钙的质量分数=0.090.12×100%=75%;故选C.