A continuous-time system that is initially at rest is described by
$$ \frac{d y(t)}{d t}+3 y(t)=2 x(t),$$
where$x(t)$ is the input voltage and $y(t)$ is the output voltage. The impulse response of the system is
- $3 e^{-2 t}$
- $\frac{1}{3} e^{-2 t} u(t)$
- $2 e^{-3 t} u(t)$
- $2 e^{-3 t}$