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提问人:网友zsx19951120
发布时间:2022-04-17
[主观题]
By the 1840s the influx of p___to the Northwest, and the flood of prospectors to Califo
rnia after 1848 had created an increasing demand for mail delivery to and from the East. (the first people to go to a particular area in order to live and work there)
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