When measuring resistance R by voltammetry, if the reading of ammeter is 0.2A and that of voltmeter is 30V, what is the resistance value of the resistance to be measured?

When measuring resistance R by voltammetry, if the reading of ammeter is 0.2A and that of voltmeter is 30V, what is the resistance value of the resistance to be measured?

Resistance to be measured r = 30 V divided by 0.2 a = 150 Ω

When measuring resistance by volt ampere method, can the resistance of the resistance to be measured be compared with that of the ammeter or voltmeter to determine whether it is external or internal? For example, the resistance of the resistance to be measured is 2000 ohm, the resistance of the ammeter is 100 ohm, and the resistance of the voltmeter is 10000 ohm. Can the result be obtained by comparing the resistance of the resistance to be measured with that of the ammeter or voltmeter, or by subtraction?

The ratio K1 of the internal resistance of the ammeter and the resistance to be measured can be compared with the ratio K2 of the resistance to be measured and the internal resistance of the voltmeter
If K1 > K2, it means that the internal resistance of the ammeter has a great influence,
If K1