(d) The stack is in the form having vertical cross section of trapezium. ∴Volume of Earth in the stack = (a)reaof cross section of trapezium × Height ∴Volume =
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(10+5)×2×8 =15×8m2 (a)ccording to the question, Volume of Earth to be spread = ((a)rea offield) × Level raised ∴Level raised =