Where rock bottom is encountered when driving a ground rod at an angle up to 45 degrees, the electrode can be buried in a trench that is at least ______ deep. a) 18 in. b) 30 in. c) 4 ft d) 8 ft See ...

Fill in the blanks with the appropriate answer. When determining ampacities of conductors for underground circuits rated between 2,001V and 35,000V, where burial depths are modified from the values ...