A battery with EMF 90.0 V has internal resistance Rb = 9.59 Ω .
a) What is the reading Vv of a voltmeter having total resistance Rv = 400 Ω when it is placed across the terminals of the battery?
b) What is the maximum value that the ratio Rb/Rv may have if the percent error in the reading of the EMF of a battery is not to exceed 5.00 %?