Q:  Find out the value of V_o by applying principle of superposition.

 Solution:         We have to calculate Vo.

             Making only voltage source active

                                    By applying voltage division rule

                                                        V₀₁=(12x2)/(7+2)=24/9V

                        While only current source is active

                        Suppose I_o pass through 2kΩ. By applying current division rule

                                                I_o= (-2)3/ (6+3) =-2/3mA       //putting the value in formula

                                               V_o2= 2x-2/3           // V=IR

                                                         =-4/3 volts

                        So,                  V_O=V_o1+V_o2

                                                   =24/9 - 4/3 =4/3 Volts