Find the B-type expanded uncertainty (coverage factor k = 2) by measurement of DC voltage
using a digital voltmeter, if the range of measurement of the voltmeter is 0.3 V and the error of
the voltmeter is given as ± 0.1 % of reading ± 0,05 % of full range. Reading of the voltmeter is
30 mV. [0.208 mV]