Answer:
![V=588\ ft^3](https://img.qammunity.org/2021/formulas/mathematics/college/6ys5p75gvyumcy2bryqkcm7r9zrsu5bdg8.png)
Explanation:
You need to use the following formula to calculate the volume of Triangular prism:
![V=ah](https://img.qammunity.org/2021/formulas/mathematics/college/pj3umogaee8cii6ebksclpobgch8n19zz7.png)
Where "a" is the area of one triangular base and "h" is the height of the triangular prism.
Calculate "a" with this formula:
![a=(bH)/(2)](https://img.qammunity.org/2021/formulas/mathematics/college/pdphq02rnl42r0totzuedhd3aule3tqvdb.png)
Where "b" is the base of the triangle and "H" is the height.
In this case:
![b=14\ ft\\H=4\ ft](https://img.qammunity.org/2021/formulas/mathematics/college/9etgxavw5a7g7l6rfk96730nuw6i8k651u.png)
Then, substituting values, you get that the area is the following:
![a=((14\ ft)(4\ ft))/(2)\\\\a=28\ ft^2](https://img.qammunity.org/2021/formulas/mathematics/college/14o54x64n2d1turqfoz39sd6a1ncl7fzs7.png)
Finally, you must substitute values into the formula for calculate the volume of the triangular prism, and you also must substitute
, which is its height:
![V=(28\ ft^2)(21\ ft)\\\\V=588\ ft^3](https://img.qammunity.org/2021/formulas/mathematics/college/fwuzz39sdioes9zp1rfg6edhdlze9xmrce.png)