A $50$ kg boy stands on a platform spring scale in a lift that is going down with a constant speed of $3\frac{m}{s}.$ If the lift is brought to rest by a constant deceleration in a distance of $9$ m $,$ What does the scale read during this period? $($Take $g=9\mathrm{.}8\frac{m}{s^2})$

$($a$)500$ N

$($b$)465$ N

$($c$)515$ N

$($d$)$ Zero