Final answer:
To join copper and galvanized steel, a brass converter fitting or di-electric union should be used to avoid rapid corrosion caused by the contact of dissimilar metals. Option D is the correct answer.
Step-by-step explanation:
Copper and galvanized steel can be joined by specific methods to avoid rapid corrosion due to the electrochemical reactions between dissimilar metals. The correct methods for joining these materials are:
- Brass converter fitting - This serves as a sort of bridge between the two metals without causing a galvanic reaction.
- Di-electric union - This fitting is designed to prevent galvanic corrosion by using insulation to separate the two metals, often combined with a non-conductive gasket or washer.
The correct answers are both a and b, indicating that either a brass converter fitting or di-electric union would be suitable to join copper and galvanized steel. It's essential to use these methods to prevent the galvanic cell formation that can lead to rapid corrosion, as experienced when dissimilar metals are in contact with each other in the presence of an electrolyte.