To limit cur rent chopping in vacuum circuit breakers, the contact mat

1.	To limit cur rent chopping in vacuum circuit breakers, the contact material used has
A.	high vapour pressure and low conductivity properties
B.	high vapour pressure and high conductivity properties
C.	low vapour pressure and high conductivity properties
D.	low vapour pressur e and low conductivity properties
Answer» E.

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To limit cur rent chopping in vacuum circuit breakers, the contact material used has

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