Explain the difference between trade barriers and migration barriers.

(1) which phrase describes an important agricultural change that occurred during the mississippian period? (a) first cultivation of wild grains (b) expansion of marsh elder farming (c) spread of corn agriculture (d) gathering of nuts and berries (2) which group of native americans use northwestern arkansas as it’s traditional hunting grounds? (a) osage (b) quapaw (c) woodland (d) caddo

On venus, which of the following drives geological change? a. hurricanes b. volcanoes c. tsunamis d. earthquakes

Which of the following is not a pillar of the nuclear proliferation treaty? nonproliferation reduction of nuclear weapons by 85-90% right to peacefully use nuclear power disarmament