Respuesta :

We will have the following:

We will recall that the surface area of a sphere is given by:

[tex]A_s=4\pi r^2[/tex]

So, the surface area of the given sphere will be:

[tex]\begin{gathered} A_s=4\pi(\sqrt{\frac{7}{3.14}})^2\Rightarrow A_s=4(3.14)\ast\frac{7}{3.14} \\ \\ \Rightarrow A_s=4\ast7\Rightarrow A=28 \end{gathered}[/tex]

So, the surface area of the sphere will be 28 yd^2.

*The reason we can use "mental math" is that we are using an approximation of pi, which makes it so it cancels with the 3.14 in the denominator after a point; leaving a simple multiplication at the very end.