An object slides on a level floor. It slows and comes to a stop with a constant acceleration of magnitude $2\mathrm{.}4\frac{m}{s^2}.$ What is the coefficient of kinetic friction between the object and the floor?

$0\mathrm{.}24$

$0\mathrm{.}48$

$0\mathrm{.}12$

$0\mathrm{.}00$