All reducing and oxidising agents in just 75 minutes

Which of the following acts as both reducing and oxidising agents ?

Assertion : A substance which gets reduced can act as reducing agent . Reason : As oxidising agent itselt gets reduced.

Name the substance oxidised, reduced, oxidising agent and reducing agent in the following reaction : Zn(s) + FeSO_(4)(aq) to ZnSO_(4)(aq) + Fe(s)

H_(2)S acts only as reducing agent while SO_(2) can act both as a reducing agent and as an oxidising agent. How will you account for it ?

Whenever a reaction between an oxidising agent and reducing agent is carried out