classify this list into primary,seconadry tertiary activities: sell clothes,gold mining,air traffic control?

Answer 1

Gold Mining is a primary activity, as it is an occupation that depends directly on mother nature, and not on another person doing something else.
Selling clothes is secondary activity, as it depends on other human activity like growing cotton (or other raw material), manufacturing clothes etc. Strictly speaking, it should be considered as a tertiary activity.
Air traffic control is tertiary activity, as it is done to support a secondary activity (flying aeroplane).