Answer:
The inexpensive method for turning iron ore into steel was developed by Sir Henry Bessemer
Explanation:
The Bessemer process was the first inexpensive industrial process for the mass production of steel from molten pig iron. It was developed before the development of the open hearth furnace. The process involved blowing air through molten pig iron to remove impurities and convert it into steel. This method revolutionized the steel industry and made steel production more affordable and efficient.
