Only three colours are needed.
One blue square touches all three red squares.
Another blue square touches only two red squares.
A yellow square touches only one blue square.
b. This solid has five pieces:
There is one square, this clips to all the pieces.
The isosceles triangles are red and green.
The edges of the red shapes do not touch red shapes.
Only red, green and blue shapes are used.
NB Almost any shape/solid that is constructed can be represented
as a set of clues.