The multimeter is able to measure a number of electrical quantities. In which roles "ammeter, voltmeter, Ohmmeter) does it have the largest and smallest resistance, and why?
Ammeter is used to measure the electric current, as it is connected in series and it shouldn't affect on the circuit , the device has the smallest resistance. With voltmeter the voltage can be measured. It's connected in paralel and the current shouldn't flow through it in ideal case, so the voltmeter must have the largest resistance. Ohmmeter is used to measure the value of resistance of circuit's chain.