I _____ it as a basic principle of the company that suppliers of raw materials should be given a fair

price for their products.[ ]

A. make      

B. look

C. take            

D. think

现代地理学经过了哪些发展历程？（）

A.计量革命

B.行为革命

C.生态思潮

D.统一地理学和大地理思潮

E.信息革命