From a distance of $10cm,$ a proton is projected with a speed of $v=4\mathrm{.}0{10}^6\frac{m}{s}$ directly at a large, positively charged plate whose charge density is See

below.$)$

$($a$)$ Does the proton reach the plate?

Yes

No

$($b$)$ If not, how far from the plate $($in $cm)$ does it turn around? $($If the proton does reach the plate, enter zero.$)$

$1cm$