已知NH4NO3和KH2PO4固体混合物中氮元素的质量分数为28%,则混合物中KH2PO4的质量分数为( )
A.20%
B.25%
C.85%
D.80%
答案:A
用所给单词的适当形式完成句子。
1. Did you find it hard __ (pass) the exam?
2. Are you ready __ (speak) in the public place?
3. It __ (be) five years since we met last time.
4. Every parents hopes __ (see) their children's progress.
5. When the teacher came in, all the students stopped __ (talk) and listened
to the teacher.
以腰膝酸冷,性欲减退,夜尿频多与虚寒症状共见为辨证依据的证候是()
A.肾阳虚证
B.肾气不固证
C.肾虚水泛证
D.肾精不足证
E.肾阴虚证