The arc is buried beneath a layer of flux and is not visible to observers:.A. Submerged Arc Welding (SAW).B. Gas-Metal Arc Welding (GMAW).C. Shielded Metal Arc Welding (SMAW).D. Flux-cored Arc Welding (FCAW).

The answer is explained below

Explanation:

Submerged Arc welding is arc welding process. Its first patent was filed in 1935.

It is used in industries in which long welds and thick steel sheets are involved. In this processes a welding joined is formed between steel components by using electrical arc that is submerged under a layer of powdered flux.

The electrode used in submerged arc welding are bare round wires having diameter of 1.5mm to 10mm. It is continuously fed during the welding. TIG welding is the strongest welding.

levels of production can be increased by technology while holding labor and capital constant, because increased technology makes the production process more efficient. subsequently, the lras curve is almost a vertical line, that can shift to the right, with an increase in technology.

the relationship between the lras curve and the ppc is that both can make the economy could grow. the ppc achieves that when it shifts outward because of more resources or technological advances while the lras curve shifts if more resources are developed or if there are technological advances.

the lras curve is a vertical line at an output level that represents the number of goods and services a nation can produce over a sustained period using all of its productive resources as efficiently as possible with all of the current technology available to it.

the production possibilities frontier (ppf) is a graphical device that is used for economic analysis of production decisions because the ppf measures the maximum possible combinations of two goods that an economy is capable of producing with its currently available resources and technology.

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