Redox reactons.

2) Which of the following is a Redox reaction? If the reaction is a redox reaction, identify which element is oxidized and reduced?3) Circle and label the oxidizing and reducing agents.a) Hg2(NO3)2 (aq) + 2 KBr (aq) ? Hg2Br2 (s) + KNO3 (aq)b) 4 Al (s) + 3 O2 (g) ? Al2O3 (s)c) CaO (s) + CO2 (g) ? CaC