What Did the Trained Engineer and Son of Former Slaves

question 37

Multiple Choice

What did the trained engineer and son of former slaves Elijah McCoy invent to improve railroad efficiency?

• A) A method to automatically lubricate gears
• B) The pneumatic brake
• C) The diesel engine
• D) The telegraph

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Definitions:

Prescription

A written direction for the preparation of a medicine.

Suppository

A solid medical preparation designed to be inserted into the rectum, vagina, or urethra, where it dissolves or melts to exert a local or systemic effect.

Narcotic

Substances that reduce pain, alter mood or behavior, and can cause sleep or stupor, often used medically for pain relief but can lead to addiction.

Ointment

A semisolid preparation usually containing medicinal substances, applied topically for therapeutic reasons.