The Two Most Persistent Sources of Oil Pollution That Keep

question 33

Multiple Choice

The two most persistent sources of oil pollution that keep oil in the marine environment for sustained periods are:

• A)Tanker and storage leak accidents.
• B)Tar balls and tanker accidents.
• C)Natural seepage and urban runoff.
• D)Urban wastes and normal operation of tankers.
• E)Refinery discharges.

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Definitions:

Bushings

Mechanical components used to reduce friction between rotating shafts and stationary support members, often serving as a replaceable lining.

Metric Thread

A standardized thread type used internationally, characterized by its metric dimensions, commonly used in bolts, screws, and nuts.

Internal Thread

The spiral grooves cut inside a hole intended to engage with an external thread, such as on a bolt, allowing for parts to be screwed together.

Plain Bearings

Bearings that operate through sliding motion between the moving surfaces, without rollers or balls, used for simpler mechanisms.