SAS Certification Prep Guide, 4th Edition

Chapter 2: Basic Concepts

1. Correct answer: c

   Rows in the data set are called observations, and columns are called variables. Missing values do not affect the structure of the data set.
2. Correct answer: a

   When it encounters a DATA, PROC, or RUN statement, SAS stops reading statements and executes the previous step in the program. This program contains one DATA step and two PROC steps, for a total of three program steps.
3. Correct answer: b

   It must be a character variable, because the values contain letters and underscores, which are not valid characters for numeric values.
4. Correct answer: a

   It must be a numeric variable, because the missing value is indicated by a period rather than by a blank.
5. Correct answer: c

   Variable ...