Balance the redox reaction
kmno4 + nh3 > kno3 + mno2 + koh + h2o

To balance the redox equation in the ion-electron method (also called the half-reaction method), the redox equation is separated into two half-equations - one for oxidation and one for reduction. Each of these half-reactions are balanced separately by the number of electrons which accepted by reduction or donated by oxidation and then combined to give the balanced redox equation.

1 a

2 d

3 a

4 c

explanation: