Volume of a prism = Base area x height
The base is a trapezium
[tex]\begin{gathered} \text{Base area = }\frac{1}{2}(a+b)h \\ =\frac{1}{2}(5+2)6 \\ =\frac{1}{2}(7)6 \\ =21ft^2 \end{gathered}[/tex][tex]\begin{gathered} \text{Volume = 21 ft}^2\text{ x 10}\frac{1}{2}\text{ ft} \\ =21\text{ x }\frac{21}{2} \\ =220.5ft^3 \end{gathered}[/tex]
