Two $1\mathrm{.}8$ g plastic buttons each with $47$ nC of charge are placed on a frictionless surface $2\mathrm{.}5$ cm $($measured between centers$)$ on either side of a $4\mathrm{.}8$ g button charged to $250$ nC $.$ All three are released simultaneously.

$($A$)$ How many interactions are there that have a potential energy?

$N=3.$

$($B$)$ What is the final speed of the left button?

$v_{\text{l}\text{e}\text{f}\text{t}}=,\frac{m}{s}$

$($C$)$ What is the final speed of the right button?

$v_{\text{r}\text{i}\text{g}\text{h}\text{t}}=,\frac{m}{s}$

$($C$)$ What is the final speed of the $4\mathrm{.}8$ g button?

$v=\frac{m}{s}$