Final answer:
The color stripe on Type "K" hard-drawn copper tubing is green, which serves as an identifier for this specific type of copper piping used in plumbing, and distinguishes it from other types such as Type L and M.
Step-by-step explanation:
The color stripe on Type "K" hard-drawn copper tubing is typically green. Type K tubing, a designation for a particular size and wall thickness of copper piping, is primarily used in plumbing applications. This type of copper tubing is known for being malleable and ductile, which means it can be bent into shapes without breaking and stretched into thin wires, respectively. Its green color stripe helps identify it among different types of copper pipes, such as Type L (blue stripe) and Type M (red stripe), which have different wall thicknesses and uses.