单项选择题 The present voyage of my ship began at the port of Shanghai after loading 8 000 tons of Cargo on board and ended after discharging the Cargo at the port of Hong Kong，which was（）.

单项选择题 The height of a VHF radio antenna is more important than the power output wattage of the radio because（）.

单项选择题 The generators on your rig have shut down，leaving you without navigation lights. Which emergency signal would you transmit over the VHF radio to alert vessels in the area of your predicament? （）