Part 1 :
The top left colour is a dark, slightly vibrant green.
The top right colour is a light, faded greyish blue.
The bottom left colour is a slightly desaturated yellow.
The bottom right colour is a light faded red.
Part 2 :
Pair 1 : Colour 1 is more satrurated, darker and redder than colour 2.
Pair 2 : Colour 1 is less saturated. lighter and greyer than colour 2.
Pair 3 : Colour 1 is more saturated, brighter and pinker than colour 2.