A manual metal arc-welding operation is performed on mild steel with a melting temperature of 1776 K at a voltage of 25 V and a current 200 A. The heat transfer factor is 0.90 and the melting factor 0.75. 1.1. Calculate an approximate value for the melting energy per unit volume for the steel plates. [2 points] 1.2. Determine (in Watts) the rate at which heat is delivered to the weld such that it contributes to melting. [2 points] 1.3. Determine the volume rate of metal welded. [2 points] 1.4. If the torch moves at 10 mm/sec to form a butt weld between two sheets of steel, what cross-sectional area of weld will be produced with these process settings? [2 points] 1.5. Discuss the relative merits of manual metal-arc welding, submerged arc welding, and metal inert-gas (MIG) welding. Consider factors such as speed, safety, the required degree of manual skill, relevant applications, and any need for post-processing of the welded assembly. [4 points] 1.6. Explain the purpose and function of flux in a welding process. [2 points] 1.7. Explain the purpose and function of a shielding gases such as argon in a MIG or TIG process. [2 points]