Which equation is the CORRECT representation of the process shown below?
1
QA1-2 + WA1-2 = QB2-1 + WB2-1
2
QA1-2 - WA1-2 = QB2-1 - WB2-1
3
QA1-2 + QB2-1 = WA1-2 + WB2-1
4
QB1-2 - QA1-2 = WB2-1 - WA2-1
Which equation is the CORRECT representation of the process shown below?