单项选择题
A.the light is characterized as alternately flashing
B.the lighthouse has lost power and has switched to emergency lighting
C.it is the identifying light characteristic of the lighthouse
D.you have entered an area of shoal water or other hazard
单项选择题 You are the first vessel to arrive at the scene of a distress. Due to the volume of traffic on the radio，you are unable to communicate with the vessel in distress. Which action should you take?（）
单项选择题 You are on a multiple-product chemical tanker with orders to load diethylamine. What is NOT a requirement for transporting this cargo?（）
单项选择题 You are on a multiple product tanker and carrying methyl acrylate，diethanolamine，and triethylamine. Which statement is TRUE?（）