Preheat oven 350°F (180°C). Prepare cake mix as directed on package, stirring in orange extract. Divide batter evenly among 4 bowls. Tint each bowl a different color. Stir 50 drops (about 1/2 teaspoon/2 ml) red, green or blue food color into each of 3 of the bowls. Stir 25 drops (about 1/4 teaspoon/1 ml) yellow food color into last bowl.