The munsell color model was the first color model to do what? a. use numbers to describe colors. b. use additive color mixing. c. use rgb as primary colors. d. use a color wheel. 2. what is value? a. the lightness or darkness of a color. b. the intensity of a color. c. the number of colors being used in a 2d artwork. d. the difference between two colors. 3. the range of values of a specific color is called a. contrast. b. gradation. c. chiaroscuro. d a color model.

1. The correct answer should be A. use numbers to describe colors.
If you take a look at the image I've attached below, you will see that this model is used to show colors according to three color dimensions, which are hue, value, and chroma. Additionally, each of the colors is numbered for better and easier understanding. 

2. Value is A. the lightness or darkness of a color.
As I've already mentioned, colors have three dimensions: hue, chroma, and value. Hue refers to the actual color of a color, its tint, what you see when you look at a color. Chroma is the saturation - how bright or dull a color is. Value is similar to that - it refers to whether a color is dark or light.

3. The correct answer is gradation.
Gradation is the term which refers to the range of colors. This range may start from lighter to darker hues of a color, or vice versa, but there is a steady increase/decrease in the value of that particular color, which is known as the gradation - they gradually become lighter or darker.

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