China's cultivated land area is about 1.82 million square kilometers. China's current population is 1.3 billion. How many square kilometers is the per capita cultivated land area? How many square kilometers is one millionth of the per capita cultivated land area? It is about the same as those around us? (the results are expressed by scientific counting method)

China's cultivated land area is about 1.82 million square kilometers. China's current population is 1.3 billion. How many square kilometers is the per capita cultivated land area? How many square kilometers is one millionth of the per capita cultivated land area? It is about the same as those around us? (the results are expressed by scientific counting method)

The per capita cultivated land area is 182 × 10 ^ 4 ^ (13 × 10 ^ 8) = 1.4 × 10 ^ (- 3) square kilometers
The per capita cultivated land area is 1.4 × 10 ^ (- 3) / (10 ^ 6) = 1.4 × 10 ^ (- 9) square kilometers
1.4 × 10 ^ (- 9) square kilometers = 14 square centimeters
(think about what you have around you. The area is about 14 square centimeters.)

The reason why the area of cultivated land is enlarged but the total grain output is decreased

Natural disasters, cultivation level and other reasons may cause the yield per unit area to decrease. The reason for the increase of area and the decrease of total yield can only be the decrease of yield per unit area