Final answer:
A soldered joint is created with metallic mixtures or alloys that melt between 800° F and 200° F, ensuring a gas-tight seal.
Step-by-step explanation:
According to the provisions of the rule, a soldered joint is a gas-tight joint obtained by the joining of metallic mixtures or alloys that melt below 800° F and above 200° F. This specification ensures a strong bond without requiring excessively high temperatures that could compromise the integrity of the metals being joined. Soldering is typically used for creating joints in electronics, plumbing, and other applications where a secure, long-lasting connection is necessary. Therefore, the correct answer is B) 800° F and above 200° F.