For the circuit shown in Figure 20.87, which consists of batteries with known emf and ohmic resistors with known resistance, write the correct number of energy-conservation and current node rule...

For the circuit shown in Figure 20.87, which consists of batteries with known emf and ohmic resistors with known resistance, write the correct number of energy-conservation and current node rule equations that would be adequate to solve for the unknown currents, but do not solve the equations. Label nodes and currents on the diagram, and identify each equation (energy or current, and for which loop or node).