Answer:
Construction of infrastructures and Manufacturing of military equipment
Step-by-step explanation:
The factors that caused steel production to increase from 13,000 tons in 1860 to 28 million tons in the first decade of the twentieth century was "Construction of infrastructures and Manufacturing of military equipment."
This is evident in the fact that the construction of infrastructures such as big bridges, railroads, skyscrapers, and ships was known to consume a lot of steel products during their construction
Similarly, the manufacturing of Military equipment such as weapons, towards World War I and II consumed a lot of steel products.