State Kirchhoff's rules. Use these rules to write the expressions for the currents `I_1,I_2` and `I_3` in the circuit diagram shown in Fig.

Explanation

In the network given here as per Kirchhoff.s first law, we have
`I_3 = I_1 + I_2` ....(i)
In loop ECDEF, we have
`- 1- 3I_2 - 2I_3 + 4 = 0`
`rArr 2I_3 + 3I_2 = 3 ` ...(ii)
Again in loop EABFE, we have
` - 2 - 4I_1 - 2I_3 + 4 = 0`
` rArr 2I_3 + 4I_1 = 2 ` ...(iii)
On solving these equations, we get `I_1 = 2/13 A, I_2 = 7/13 A` and `I_3 = 9/13A`