Calculate the electric power developed in the circuit you

Question

I am stuck on three questions from a lab report.  I know the equation for the first question but not sure which values to use for I to find the internal resistance of the battery. The second question I am not sure what to use in this circuit to find electrical power. The last question I have no idea.

1. Evaluate the internal resistances of the batteries using the obtained data.

(I figured out the equation for the first battery would be ε= V-Ir and then the same for the second battery in the circuit. But I am not sure of which current to use based on all my measurements.)

2. Calculate the electric power developed in the circuit you measured. (No idea what to use for this circuit since P = W/t)

3. Could you calculate the electric power developed in the circuit, if the resistances of the resistors are unknown Explain.

Actual: R₁=102 Ω, R₂=198 Ω, R₃=295 Ω and R₄ =506 Ω. We didn't measure the atual for the two EMF sources so I guess I would need to use the given values.

Measured Data for the circuit.

Junction B (IBF + IBAGF + IBCDF = 0)		Junction F (-IGF + -IBAGF + -IBCDF = 0)
IBAGF (mA)	7.50	IBAGF (mA)	-7.46
IBF (mA)	6.42	IGF (mA)	-6.39
IBCDF (mA)	-13.84	IBCDF (mA)	13.88
Experimental Net Current (mA)	0.08	Experimental Net Current (mA)	0.03
Junction B and F Positive Currents		Junction B and F Negative Currents
IBAGF (mA)	7.50	IBAGF (mA)	-7.46
IBF (mA)	6.42	IGF (mA)	-6.39
IBCDF (mA)	13.88	IBCDF (mA)	-13.84
Net Positive Currents	27.80	Net Negative Currents	-27.69
Percent Difference (Pos/Neg)	0.40%

For the loop ABFGA:		For the loop BCDFB:		For the loop ABCDFGA:
R3 IBAGF	2.198	R1 IBCDF	1.417	R3 IBAGF	2.199
R2 IBF	-1.267	R2 IBF	1.266	R1 IBCDF	1.418
R4 IBAGF	3.777	?2	-2.685	R4 IBAGF	3.778
?1	-4.709	Net Voltage	-0.002	?1	-4.712
Net Voltage	-0.001	Percent Difference (Bat/RES)	0.07%	?2	-2.687
Percent Difference (Bat/RES)	0.02%			Net Voltage	-0.004
				Percent Difference (Bat/RES)	0.05%