简述体育教学内容

A. avoid any swing in a restricted space
B. prevent to touch with other vessels
C. make a convenience of cargo discharging

A. 岗位培训
B. 师徒培训
C. 交流参观
D. 课堂讲授

A. 氨制冷
B. 氟利昂制冷
C. 溴化锂制冷