The answer to the question is : B: 6;6 <span>There are __6__ different types of air masses that coming from _6___ different locations that influence the weather in North America., namely : a) </span>Continental Polar ; Large sub polar land area b) Continental Arctic ; Canada, United States c) Continental Antarctic ; Antartica d) Continental Tropical ; Sahara, Arabian & Australian Deserts e) Maritime Polar ; Polar Oceans f) <span>Maritime Tropical ; Rocky Mountains</span>
As the resources in the world are distributed unequally, the crops and the ability to grow them in specific environmental conditions such as near the river valleys, on the foothills of the mountains and near the flood plains differ worldwide as many places don't have enough sunlight,
many places is too warm or hot for there growth and other place are too cold or are locates at great heights. Variation thus exists in the cropping patterns and the cropping intensity as they need specific conditions as climate, weather, and soil properties.
Many of the earlier civilizations developed and prospered near the river valleys.
