AP Physics C 2017

(^1) Resistivity would be given on the AP exam if you need a value. Nothing here to memorize.
(^2) The current through R 5 must be the same as through R 1, because both resistors carry whatever current came directly from the battery.
The current through R 3 and R 4 can be determined from Kirchoff’s junction rule: subtract the current in R 2 from the current in R 1, and that’s
what’s left over for the right-hand branch of the circuit.