Answer:
5,864.31 ft²
Explanation:
The area of a full circle is given by:
![A_C=\pi r^2](https://img.qammunity.org/2021/formulas/mathematics/college/346y648ynbbbhtb7wkdjfrrg5mu0joqzgr.png)
Since the room is a circular sector with a central angle of 105 degrees and knowing that a circle has a central angle of 360 degrees, the area of the room is:
![A_R=(105)/(360) \pi r^2=(105)/(360) \pi 80^2\\A_R = 5,864.31\ ft^2](https://img.qammunity.org/2021/formulas/mathematics/college/nj0e2zme7eme3tu887rstvnhxilm2hqtbf.png)
The area of the carpet to be laid is 5,864.31 ft².