Using a voltmeter as an ammeter, using an ammeter as a voltmeter.
The Ammeter is measuring volts across the light bulb 9.9V (1ma=10V). The voltmeter is measuring the current through the light bulb plus the ammeter, 100mv=100ma. Use Ohm's Law. Pick resistor values that (1) convert the value of interest into a value within the meter's range, (2) have the least effect on the circuit so as to avoid the "measurement" influencing the meter reading.
