The correct answer is: [C]: " 491 ft³ " .
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Step-by-step explanation:
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Note the formula/equation for the volume of a pyramid:
Volume of a pyramid, "V" :
V = (⅓) *(base area) *
(perpendicular height; that is height measured from center of base to apex) ;
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base area (which is a square, in this case) =
length * width = 8 ft * 8 ft = 64 ft ² ;
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perpendicular height = 23 ft ;
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V = (⅓) * (64 ft ²) * (23 ft) ;
= [(64 ft ²) *(23 ft)] / 3 = 1472 ft³ / 3 ;
= 490. 66666... ft³ ; (that is; "490 ⅔ ft³ ") ; which is closest to (rounds up to):
Answer choice: [C]: 491 ft³ .
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