The Use of the Airplane as a Device to Deliver

question 65

Multiple Choice

The use of the airplane as a device to deliver mail did not become popular until

• A)government grants provided for training pilots.
• B)Charles Lindbergh flew around the world,showing that it was safe.
• C)after World War I.
• D)it was shown to be a quicker and cheaper way to deliver it.
• E)Amelia Earhart became the first female pilot to do so.

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Emigrants

People who leave their country of origin to live permanently in another country.

Immigrant Workers

Immigrant workers are individuals who have moved from one country to another for the purpose of employment.

Substitute Resources

Productive inputs that can be used instead of other inputs in the production process; resources for which an increase in the price of one leads to an increase in the demand for the other.

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Productive inputs that are used jointly with other inputs in the production process; resources for which a decrease in the price of one leads to an increase in the demand for the other.