The PCB 1 wherein the metal having {HEAD ~ a conductivity} lower than {TAIL ~ the conductivity} of copper is nickel 
lower than
The PCB 1 wherein the metal having { HEAD ~ a conductivity } lower than { TAIL ~ the conductivity } of copper is nickel
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH