Which trail acted as a mail route that connected the West Coast to the eastern half of the United
States?

Oregon Trail

Explanation:

The Oregon Trail was a 2,000-mile, historic east-west wagon route and emigrant trail that connected the Missouri River to valleys in Oregon and locations in between. The eastern part of the trail spanned part of the future state of Kansas and nearly all of what are now the states of Nebraska and Wyoming.

the answer is:

b) to show the progression of inventions that took place in the bicycling industry.

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many scientists' predictions of climate change include: warmer temperatures, rising sea levels, and more frequent storms.

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