Final answer:
Oxyfuel-gas welding offers high heat concentration and precise flame control, making it suitable for metalworking and other applications such as in healthcare and space exploration. Fuel costs and the level of skill required can vary, contrary to the belief that it requires minimal skill.
Step-by-step explanation:
Oxyfuel-gas welding is a common process used in metalworking that involves the use of a torch to melt and join metal pieces. The advantages of oxyfuel-gas welding include high heat concentration, which allows for efficient melting of metals, and precise control of the flame, enabling detailed work. Fuel costs can be moderate to low depending on the specific gases used; however, acetylene, which is commonly utilized for its high heat output, is generally more expensive than alternatives like propane.
While there is a belief that oxyfuel-gas welding requires minimal skill, it actually demands significant training and practice to ensure safety and achieve high-quality welds. The process typically employs compressed acetylene and oxygen mixtures to produce flames hot enough for welding, with applications extending beyond metalwork to include the medical field for oxygen delivery and even the space industry as an oxidizing agent in rocket engines.
Therefore, the advantages of oxyfuel-gas welding would most accurately be a (High heat concentration) and c (Precise control of the flame), as they directly relate to the process's capabilities.