The tertiary colours in the colour wheel sit between a primary colour and a secondary colour. They are the six 'in-between' colours. In the colour wheel, tertiary colours sit between the two ...

In medicine, there are four levels of care: primary, secondary, tertiary, and quaternary. The levels of care refer to the complexity of the medical cases that healthcare providers treat and the ...

They include the primary ... secondary sector companies. Tertiary sector companies are service providers. They may be retailers, financial service providers, or entertainment companies. Quaternary ...