企业业务单位计划的核心是（）。

A. pull the nozzle handle all the way back toward the operator
B. pull the nozzle handle back to a position where the handle is perpendicular to the plane of the nozzle
C. push the nozzle handle forward as far as it will go
D. insert a fog applicator between the fire hose and nozzle

A. 遵义会议
B. 六届六中全会
C. 六届七中全会
D. 党的七大

A. 哥白尼
B. 哥伦布
C. 麦哲伦
D. 瓦斯科·达·伽马