水玻璃的模数
参考答案：
水玻璃组成中，氧化硅和氧化钠的分子比n称为水玻璃的模数。
---Have you had lunch? ----_____.
A．Yes, How about you.
B．It’s very kind of you to invite me, but I’m afraid I hve no time.
C．Yes, why do you ask me?
D．All the dishes taste well.Thank you very much
托马斯·阿奎那
