Study the following reactions.
a) CH4(g)+2O2(g) ---> CO2(g)+2H2O(l)
b) Pb(NO3)2(aq)+2NaBr(aq)---> PbBr2(s)+2NaNO3(aq)
c) 6FeSO4(aq)+3Cl2(g)----> 2Fe2(SO4)3(aq)+2FeCl3(aq)
In each case, state
i) whether the reaction is redox or not
ii) the formula of the oxidizing agent (if applicable)
iii) the formula of the reducing agent (if applicable)
iv) the name of the element which is oxidized (if applicable)