It would be more accurate to calculate using only the arable land because only the arable can be surely said to be suitable for the cultivation of crops.
<u>Explanation:
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It is preferable to calculate the amount of agricultural yield that can be obtained from a specific area by taking into consideration only the land that is arable because the land other than arable land cannot guarantee the expected produce as it is not deemed to be suitable for farming.
Arable land guarantees the expected produce owing to the fertility of the soil and the nutrients present in it that are crucial for the crop to thrive.
This is true. The homestead act gave people huge properties for a small price if they were willing to work on the field for 5 years. After 5 years it would become their and they could do with it as they wished.
Many oil rich nations in the middle east must import fresh water this is due to the reason that all the natural resources are not present in a particular region. Each region as different degree of natural resources . Hence places with oil mines have spares water resources and hence need to import water instead of oil.