The voltage drop across R3 is common to both legs of the circuit.
Use simultaneous equations.
15 = V1 +v3
10= V3 +v2
(15-10)= V1 +v2
Solving reveals V1 = 5V
V3 = 10V
v2 = 0V
Now u can work out the currents using V=IR.
Now u can work out the Power using P=VI.
Spice analysis claims otherwise...seems there's a polarity issue with V2, depending on how u look at it its -5V to the left side of the circuit and +5V to the right side.
That causes V3 to be 5V, v2 is either +5 or -5 depending on how u look at it and v1 is 10V.