Which of the following is considered standard numeric data?

Standard numeric data typically refers to values that can be represented in a straightforward numeric format, which can include integers, decimals, and scientific notation. In this context, the correct answer is a representation of a number in scientific notation, specifically 4.2E-2. This indicates a value of 0.042, which is clearly a numeric data type.

Numeric data is often used in various types of calculations and statistical analyses, making its correct representation essential in programming environments, including SAS. Other representations, such as currency with a dollar sign and commas, or date formats, do not fit into the standard numeric data category. For instance, "$2,312" is formatted for currency and entails additional formatting beyond a simple numeric value. Similarly, "10/12/05" is a date representation and not a standard numeric value. The number "2,313," while it represents a whole number, includes commas that may prevent it from being classified strictly as standard numeric data in certain programming environments.

Therefore, 4.2E-2 stands out as it maintains the integrity of a numeric representation, making it suitable as standard numeric data in SAS and other programming languages.