Which statement about plate thickness is true?

• A. Aluminum weighs about as much as sheet metal per square foot.
• B. Copper is gauged by pounds per square foot.
• C. The thickness of plate is indicated in fractions of an inch.
• D. Stainless steel is weaker than iron.

Answer: (C)

The main idea is that plate thickness is specified in inches, usually using fractional inches for common stock. This convention makes it easy to specify and read thickness for fabrication, matching drawings, and choosing bending radii or welded sections. For example, you’ll see plates described as 1/4", 3/8", 1/2" thick, and sometimes in decimal inches like 0.750". The other statements mix concepts that aren’t how thickness is defined: weight per square foot depends on both material density and thickness, so Aluminum vs a generic sheet metal comparison isn’t a reliable way to state thickness; gauge describes a thickness scale for sheet metal rather than a weight measure; and stainless steel is a different alloy that is typically stronger and more corrosion-resistant than plain iron, not weaker.