Why Was the Development of Cast-Iron and Steel-Frame Construction Techniques

question 58

Multiple Choice

Why was the development of cast-iron and steel-frame construction techniques significant to the growth of cities?

• A) The growth of streetcars depended on such techniques.
• B) They were the primary engines of job growth.
• C) They allowed developers to erect high-rise buildings.
• D) They were invented by immigrant laborers.
• E) They demonstrated the value of female ingenuity.

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Definitions:

Neurotransmitters

Chemical substances released at the end of a nerve fiber by the arrival of a nerve impulse, facilitating the transmission of impulses across synapses to another nerve, muscle, or gland.

Synapse

(SIN-aps) The junction where the axon terminal of a sending neuron communicates with a receiving neuron across the synaptic cleft.

Resting Potential

The slight negative electrical potential of the axon membrane of a neuron at rest, about –70 millivolts.

At Rest

A state where an object or individual is not in motion, or is experiencing mental or physical tranquility.