$2y^{\text{'}\text{'}}+3y^{\text{'}}+y=f(t)=\{\begin{array}{ccc}0& if& t<mn>2</mn>\end{array}$

$tift2$

$y(0)=y^{\text{'}}(0)=0$

Which of the following is true?

L$$tfen birini se$$in:

A$.$ None of these

B$.L\{f(t)\}=\frac{1}{s^2}{e}^{-2s}$

C$.y(t)=1+2t+e^{-t}-2e^{-\frac{1}{2}t},t2$

D$.L\{y(t)\}=\frac{1}{s^2(s+1)}{e}^{-2s}$