If you graph a linear function, you get a line. If you graph a quadratic function, you get something called a parabola. A parabola tends to look like a smile or a frown, depending on the function. Check out this tutorial and learn about parabolas!
Orange Door Meanings. Orange is a colour associated with Mercury, which is the swiftest of the planets. Indeed the planet as the fleet-footed Roman god is symbolic of for reception, communication, perception, commerce, movement, intelligence and flexibility. With these kind of qualities, it might be a good idea to paint your business door orange.
Is there a history/meaning to a red front door? We see that a lot of old (and new) houses at least currently have red front doors, even if there is no other red trim on the house. Other than it's supposedly a good thing according to the rules of Feng Shui, is there any other symbolism or history to red front doors?