The answer is: " 28.5 ft " ; or, write as: " 28 ½ ft. " .
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Area = (1/2) *(base length 1 + base length 2) * height;
A = (½) * (b₁ + b₂) * h ;
A = (½) * (4.5 + 9.75) * 4
A = (½) * (14.25)* 4 ;
A = 2 * (14.25) ;
A = 28.5 ft ; or, write as: 28 ½ ft.
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