R = V / I.
Voltage is 621mV, Current is 690mA.
Substituting we get, R = 0.9.
Hence, 2 outer wires having less resistance (i.e. more current conduction) is connected to Ammeter. And, 2 inner wires having more resistance (i.e. less current conduction) is connected to Voltmeter.
A normal measurement probe connected to an ohmmeter will have only 2 wire with resistance, which will be added up (because in series), causing inaccurate reading.
