单项选择题 The bearing of tailshaft sealing equipment, which adopting the oil nature circulation is hot, the reason is（）

单项选择题 The tailshaft sealing arrangement found a little lube oil leaky and caused a lot of seawater into the bearing, the step should be taken as a makeshift is（）

单项选择题 When the vessel shafting are installed, the slightly inclined of the shaft line should be rectified by（）