The tool used in precision work to smooth or enlarge a slightly undersized hole, is called()
A. round out
B. round file
C. reamer
D. hole driller
()的主要作用是使水吸收热量,加热成为具有一定压力和温度的蒸汽。
A. 省煤器
B. 过热器
C. 水冷壁
A power driven vessel when towing and the length of the tow exceeds 200 meters shall exhibit during daylight hours where they can best be seen which of the following shapes? ()
A. a diamond shape
B. two cones,apexes together
C. a black ball
D. one cone,apex upward
认识的客体是()
A. 客观世界
B. 客观事物
C. 进入实践视野中的客观世界
D. 主体指向的客观事物
E. 依赖于认识中的主体