During world war 1, the United States: A. Stopped all trade with nations at war.
B. Negotiated for a peace without victory.
C. Was unable to trade because of the British blockage.
D. Became an important trading partner with the Allied Powers.

the enslaved people onboard suffered from illness with some frequency

answer: the time zones used to be whatever the local authority wanted them to be. one town might have 6am whenever the sun came up and another town had 6am 10 minutes later.  

the trains had a hard time when their orders said to be at a certain point at 6am.  

6am, but who's 6am.  

the railroads got together and set the time zones more or less along the longitude lines across the country.

explanation:

your answer would be a) no nation can be economically self-sufficient.

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