To determine what navigation lights and day-shapes must be displayed on mobile offshore drilling units under tow，you should check the（）.
American Bureau of Shipping classification rules
B. International Regulations for Preventing Collisions at Sea
C. Safety of Life at Sea Convention
D. Minerals Management Service rule
A motor enclosure which protects against falling liquids is classified as （）
A. waterproof
B. drip proof
C. spray tight
D. spray proof
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