Which statement is true?

• A. In colonial America, a master was required to provide food, lodging, clothing, and wages to the apprentice.
• B. In 1940, the Lockformer Company developed the Pittsburgh machine.
• C. World War I decreased the need for skilled workers in the sheet-metal trade.
• D. In 1884, William Dunn and Alfred Bowers stamped the first metal airplane wing.

Answer: (B)

The statement is about a milestone in sheet-metal fabrication equipment. In 1940, the Lockformer Company introduced a machine known as the Pittsburgh machine, which represented a significant upgrade in how sheet metal parts—especially ducts and seams—could be formed and joined. This development reflects the era’s move toward powered, specialized equipment that made production faster and more consistent, reducing manual labor and improving quality across parts. The other historical notes are less accurate or not aligned with common trade history: for example, WWI actually boosted demand for skilled sheet-metal workers due to defense production, and the idea of a first metal airplane wing in 1884 doesn’t align with when metal aircraft construction became widespread.