Answer: 36 ft³
Explanation:
You must apply the formula for calculate the volume of a rectangular prism, which is show below:
![V=l*w*h](https://img.qammunity.org/2020/formulas/mathematics/high-school/bk5c0k90wz33o36d101c5elshfngzreq00.png)
Where l is the lenght, w is the width and h is the height.
Given the dimensions shown in the problem, you can substitute values into the formula shown above.
Therefore, you obtain that the volume of the rectangular prims is:
![V=(9ft)(1ft)(4ft)\\V=36ft^3](https://img.qammunity.org/2020/formulas/mathematics/middle-school/8vetry969x5fia6z52bwqgmrgu2a0l9yrg.png)