Two Technicians Are Discussing Rear Main Seals

question 11

Multiple Choice

Two technicians are discussing rear main seals. Technician A says modern engines use a molded synthetic rubber lip-type seal. Technician B says modern engines use a wick or rope type seal. Who is correct?

• A)A only
• B)B only
• C)both A and B
• D)neither A nor B

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Definitions:

Pioneer Species

The first species to colonize previously disrupted or damaged ecosystems, starting a chain of ecological succession.

Climax Community

A stable community that has reached a steady state after a succession of ecological communities have evolved and there are no further major changes.

Competitive Exclusion

The ecological principle that two species competing for the same resources cannot coexist at constant population values if other ecological factors remain constant.

Paramecium Caudatum

A species of ciliate protozoan that lives in freshwater environments and is known for its slipper-like shape.