Three specific examples of the Columbian Exchange and describe the impact on people and/or the land.

American crops such as maize, potatoes, tomatoes, tobacco, cassava, sweet potatoes, and chile peppers became important crops around the world. Old World rice, wheat, sugar cane, and livestock, among other crops, became important in the New World.

Explanation: Physical and psychological stress, including mass violence, compounded their effect. The impact was most severe in the Caribbean, where by 1600 Native American populations on most islands had plummeted by more than 99 percent. Across the Americas, populations fell by 50 percent to 95 percent by 1650.

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map scale refers to the relationship (or ratio) between distance on a map and the corresponding distance on the ground. for example, on a 1: 100000 scale map, 1cm on the map equals 1km on the ground.