What do primary, secondary, and tertiary economic activities have in common?

The common thing between these three types of activities is that they form a production chain giving customers the provision of finished goods or services.

Primary production involves acquirement of raw materials for production like coal, metal, rubber tapping etc.

Secondary production involves manufacturing and assembly process that involves the use of such raw materials.

Tertiary production involves commercial services that support the production and distribution process.

All the processes occur in line with each other, where the working of one is essential for the other.