To find the radius of a sphere given its surface area, you can use the formula for the surface area of a sphere:
\[ SA = 4\pi r^2 \]
Where \(SA\) is the surface area and \(r\) is the radius.
Given that the surface area of the sphere is \(7.84\pi\) ft², you can set up the equation:
\[ 4\pi r^2 = 7.84\pi \]
To simplify, you can divide both sides of the equation by \(\pi\):
\[ 4r^2 = 7.84 \]
Next, divide both sides by 4:
\[ r^2 = \frac{7.84}{4} = 1.96 \]
Now, take the square root of both sides to find \(r\):
\[ r = \sqrt{1.96} = 1.4 \]
Thus, the radius of the sphere is \(1.4\) ft.