单项选择题
When the current flow through a copper wire increases, its （）
A.resistance will decrease B.insulation will bum C.temperature will increase D.conductivity will increase
单项选择题 When securing an AC generator, you should FIRST （）.
单项选择题 Prior to starting an AC generator prime mover, the voltage regulator cutout switch should be placed in the （）
单项选择题 The main purpose of an electric space heater installed in a large AC generator is to （）
