An isolator is installed_____________? A. to operate the relay of circuit breaker B. as a substitute for circuit breaker C. always independent of the position of circuit breakerD. generally on both sides of a circuit breaker

The material used for fuse must have_____________? A. low melting point and high specific resistance B. low melting point and -low specific resistance C. high melting point and low specific resistance D. low melting point and any specific resistance