Q1: Cast iron contains __________ percent carbon.

ANS:A - 2.5

Cast iron typically contains around 2.5% to 4.0% carbon by weight, although it can vary depending on the specific grade and intended application. Among the options provided, none exactly match this typical range. However, 2.5% carbon is closer to the lower end of the typical carbon content range for cast iron. Therefore, the closest option would be: 2.5