5 to 10%
20 to 30%
50 to 60%
70 to 80%
Answer is Wrong!
Answer is Right!
The correct answer is A. 5 to 10%.
Alumina (Al2O3) is a major component of clay, which is the main ingredient in brick earth. The percentage of alumina in a good brick earth should be between 5 to 10%. This is because alumina helps to give bricks their strength and durability. If the percentage of alumina is too low, the bricks will be weak and may crumble. If the percentage of alumina is too high, the bricks will be difficult to work with and may be brittle.
Option B is incorrect because 20 to 30% is too high a
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