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Which groups of people most directly benefited from song innovations in the song dynasty‘s open border policy?

The controlled use of fire by hominids: (a) limited the expansion of hominids into certain environments, such as dry grasslands. (b) decreased the amount of food energy available in the hominid diet. (c) contributed to geographical expansion and food production techniques in positive ways. (d) has been shown to contribute little to the digestive process of hominids.

Of the 8 territories that were brought under the flag of the united states by 1853, which one do you think was the most important addition to the growth of the united states?