Which of the following is NOT a factor toward the end of the frontier imagine?

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Explanation:

a. because the u.s. was the leading with the most technology, economy, etc. also was teamed with other allies witch boosted the economy and materials to improve technology and use it.

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question - in the 1900s there were two competing views about the environment that often pitted industrialist and conservationist against one another. how were these two competing views demonstrated by the environmental policies of president roosevelt and president taft?

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