Why _______ he like koala bears? [ ]
A. is
B. are
C. do
D. does
答案:D
产生于西方国家由卖方市场向买方市场过渡的阶段的市场营销观念是()
A.生产观念
B.推销观念
C.产品观念
D.市场观念
绘图题:画出德士古煤炭气化工艺流程。