Sphere $1$ has surface area $A_1$ and volume $V_1,$ and sphere $2$ has surface area $A_2$ and volume $V_2.$ If the radius of sphere $2$ is $8$ times the radius of sphere $1,$ what is the ratio of each of the following?

$($a$)$ the areas, $\frac{A_2}{A_1}$

$($b$)$ the volumes, $\frac{v_2}{v_1}$