农业发展的三大支柱是指（）。
A.农村
B.农业研究
C.农民
D.农业教育
E.农业推广
参考答案：B, D, E
A deep draft VLCC (100，000 DWT+) navigating in a narrow channel or canal（）.
A.draws more water than when underway in deep water
B.draws less water with an increase in speed
C.requires less power for a given speed
D.steers better under full power
Pentium的片上Cache采用统一结构还是分离结构？
