单项选择题 When loading or discharging dry mud or cement，crew members should use facial respirator masks and（）.

单项选择题 When joining the female coupling of the fire hose to the male outlet of the hydrant，you should make sure that the（）.

单项选择题 When inspecting a tank barge to see that it has all the required fire extinguishers and other safety items aboard，which of the following is the best source for determining what is required?（）