我国季风区与非季风区大致以____阴山、贺兰山____冈底斯山脉为界.
读短文,回答问题。
May: Good morning! Can I help you?
Lucy: Yes. I want some pencils and pens.
May: We have many here. Which one do you like?
Lucy: That red one, please.
May: Here you are.
Lucy: Thank you. How much is it?
May: It's cheap. It's 1 yuan.
在Na2SO4、NaCl、NaOH的混合溶液中,Na+、SO42-、OH-的个数比是8:1:2,则溶液中Na2SO4、NaCl、NaOH的物质的量之比是( )