86. What is the process of converting iron into steel by heating the iron with a controlled amount of carbon and other alloying elements called?
a) Refining
b) Smelting
c) Milling
d) Alloying
87. Which metal is commonly used for making electrical contacts and connectors in high-frequency and high-power applications due to its low electrical resistance and heat conductivity?
a) Copper
b) Aluminum
c) Silver
d) Copper-tungsten
88. What is the process of converting iron into steel by heating the iron with a controlled amount of carbon and other alloying elements in a vacuum or controlled atmosphere called?
a) Refining
b) Smelting
c) Milling
d) Vacuum-treating
89. Which metal is primarily used for making electrical contacts and connectors in electronic devices due to its low contact resistance and resistance to corrosion?
a) Copper
b) Aluminum
c) Silver
d) Ruthenium
90. What is the process of converting iron into steel by heating the iron with a controlled amount of carbon and other alloying elements in a crucible called?
a) Refining
b) Smelting
c) Milling
d) Crucible-tempering
