The Statistical Abstract of the United States is a huge annual compendium of data for the United States, and it is available online free of charge. TRUE Convenience sampling is quick but not random, and the target population is unclear.
No list is available for the unpredictable mix of departing flights, so we can't use a simple random sample. This will be followed by application of the concepts and methods to business and economic-related problems.
Judgment, systematic, and simple random Identifiable strata such as gender, ethnicity, or region can be used. An advantage of a systematic sample is that no list of enumerated data items is required.
Choosing the third person listed on every fifth page of the phone book is stratified sampling.