问题
选择题
—_______the weather like in Moscow?
—It's raining.[ ]
A. How's
B. What's
C. How does
D. What does
答案
答案:B
—_______the weather like in Moscow?
—It's raining.[ ]
A. How's
B. What's
C. How does
D. What does
答案:B
氮肥能促促使农作物的茎、叶生长茂盛,叶色浓绿.某同学发现她家花盆中的花草生长迟缓,便施用了一种氮肥.下面是该氮肥包装标签的部分文字.试根据相关信息计算:
碳酸氢铵 (NH4HCO3) 净重:50Kg 含氮量:16.8% ×××化学工业公司 |
(2)碳酸氢铵中氮元素的质量分数为______.(计算结果精确到0.1%)
(3)这包氮肥中氮元素的质量是多少______g(计算结果精确到0.1g).
(4)这种氮肥的纯度(即化肥中碳酸氢铵的质量分数)是多少?(计算结果精确到0.1%)