uppose that two system S1 and S2 are connected in parallel a) if both S1 and S2 are nonlinear, will the parallel connection necessarily be nonlinear ?...

Random Signal processing suppose that two system S1 and S2 are connected in parallel a) if both S1 and S2 are nonlinear, will the parallel connection necessarily be nonlinear ? give example b) if both S1 and S2 are time varying, will the parallel connection necessarily be time varying ? give example