Which process category do oxyfuel cutting, plasma arc cutting, and air-carbon arc cutting belong in? thermal electrical metallurgical mechanical

Oxyfuel cutting, plasma arc cutting, and air-carbon arc cutting all belong to the thermal process category. These cutting methods use heat to melt and remove metal, with oxyfuel cutting using a combination of oxygen and fuel gas, plasma arc cutting using an electric arc to ionize the gas and create plasma, and air-carbon arc cutting using an electric arc between a carbon electrode and the metal to melt it.