Older Engines with Nonhardened Valve Seats May Need a _____

question 89

Multiple Choice

Older engines with nonhardened valve seats may need a _____ substitute added to gasoline or ethanol blends to prevent premature valve seat wear.

• A) lead
• B) octane
• C) methanol
• D) MTBE

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Definitions:

Upright Position

A body posture where an individual stands or sits straight, with the spine aligned vertically.

Diaphragm

A dome-shaped muscular partition separating the thorax from the abdomen in mammals, playing a major role in breathing.

Musculomembranous Wall

The layer composed of both muscle and membrane, often referring to structures within the body such as the digestive tract.

Thoracic

Pertaining to the chest area or the thorax, the part of the body between the neck and the abdomen.