Find the Fourior Transforms of: \[ \begin{array}{ll} v(t)=P_{4}(t) e^{-j 3 t} & 4 \text { Marks } \\ v(t)=18 \cos (4 t) & 4 \text { Marks } \\ v(t)=6 r e^{-3 t} & 4 \text { Marks } \\ v(t)=-P_{1}\left