Color theory primary colors work at all is that the imperfect pigments being used have sloped absorption curves, and thus change color with concentration. A pigment that is pure red at high concentrations can behave more like magenta at low concentrations. This allows it to make purples that would otherwise be impossible. Likewise, a blue that is ultramarine at high concentrations appears cyan at low concentrations, allowing it to be used to mix green. Chromium red pigments can appear orange, and then yellow, as the concentration is reduced. It is even possible to mix very low concentrations of the blue mentioned and
Judo in Canada (brown belt). Later, when he travelled to Japan as Prime Minister, he was promoted to "sho-dan" (first-degree black belt) by the Kodokan, and then promoted to "ni-dan" (second-degree black belt) by Masao Takahashi in Ottawa before leaving office. Trudeau began the night of his famous 'walk in the snow' before announcing his retirement in 1984 by going to Judo with his sons. Other Canadian politicians and their families have also been associated with Judo. The children of Trudeau's successor in office, Brian Mulroney, also practised at the Takahashi Dojo, and Judo Canada has presented two honorary black belts to Members