Answer:
[tex] \frac{90}{360} \times 2\pi \: r \\ \frac{1}{4} \times 2 \times 3.14 \times 5 \\ \: \: \: = 7.85 {ft}^{2} \\ area = 7.85 + 75 \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: = 82.85 {ft}^{2} [/tex]