I think the answer is the first one and the last one .
So 12 = 2 + 20t -5t^2
5t^2 -20t + 10=0
t^2 -4t + 2 = 0
Use quadratic formula to solve
Answer: <span>2,856 ft³ .</span>
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Volume of a rectangle prism = BASE AREA * height ;
The "base area" is the area of the rectangle:
(Area = length width; or, "L * w").
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So, volume of a rectangular prism = L * w * h ; h = height ;
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V = L * w * h = 12 ft * 17 ft. * 14 ft = 2,856 ft³
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