Red is a primary color and cannot be produced by mixing other colors. Red, blue and yellow are the three primary colors. Only secondary and tertiary colors can be fabricated by mixing the appropriate colors together.
A fact is a piece of information that can be strictly defined and proved true. An opinion is a statement that expresses a belief, value, or feeling. An opinion cannot be proved true or false. For example, a person's age is a fact, but if someone is asked how old they feel, it is impossible to prove the person's answer to be true or false.
An opinion is a belief or judgment that falls short of absolute conviction, certainty, or positive knowledge; it is a conclusion that certain facts, ideas, etc., are probably true or likely to prove so: political opinions; an opinion about art; In my opinion this is true.