The difference in the areas of the cross sections is 20 m².
Area of the first cross section
Base= 8 meters
Height= 10 meters
Area of the triangle = 1/2b×h
Area =1/2× 8×10
Area = 40 m²
Area of the second cross section
Base= 12 meters
Height= 10 meters
Area of the triangle = 1/2b×h
Area =1/2× 12×10
Area = 60 m²
Difference in the areas of the cross sections
Difference= 60 - 40
Difference= 20m²
Inconclusion the difference in the areas of the cross sections is 20 m².
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