2540=2.5÷4=20：32=0.625=40：64．
故答案为：40，2.5，32，40．
—Have you found anywhere to do your research?
—Yes. It's the company my elder brother belongs.[ ]
A. there
B. that
C. what
D. where
原理油中杂质对炭黑生产有影响吗？如何解决？
