For a mass$-$spring$-$damper system the governing equation is:

$m{x}^{}+c{x}^{}+kx=F(t)$

$m=4kg$

$c=3N^{*}\frac{s}{m}$

$k=72\frac{N}{m}$

$F(t)=0\mathrm{.}7N$

Determine the position, using $x.x$ format, at $t=4sec$ if the system starts from $x(0)=x_o$

$=0\mathrm{.}3m$ with an initial velocity of $0\frac{m}{s}$