This exercise is about mixing colors and the effect which has adding white or black to the color. I did this exercise with both acrylic paints and with water color paints. The first picture is done with watercolors. I used my waterbrush to apply these colors. This is a brush which as a compartment for water in the brush. By squeezing the compartment, the water flows into the hairs of the brush. I love this brush as it makes color mixing much easier than with a regular brush. The first section of the colors was done by adding white to the color. The second section has black added to it.