投资活动主要由( )投资交易组成。
A.合规性
B.权益性
C.债权性
D.风险性
参考答案:B,C
Alice _____ in a book that the city she lives in was _____ one hundred years ago.
A.found, found
B.founded, founded
C.founded, found
D.found, founded
高炉对风口装置的要求有哪些?