单项选择题
A.The propeller hub taper and shaft keyway should be inspected for cracks or corrosion
B.The stern bearing alignment with the stern frame should be checked
C.The interior of the stern tube should be inspected for leaks
D.The shaft liner should be removed and inspected
单项选择题 Which of the listed types of files is the best for producing a fine finish on metal?（）
单项选择题 The tool used in precision work to smooth or enlarge a slightly undersized hole, is called（）
单项选择题 Reheating a hardening component to a temperature lower than the hardening temperature and then cooling it is known as （）