Final answer:
The unit scale is a standard unit of measurement used to represent actual dimensions in a model or drawing. It is calculated by adding the width and height of the frame size together.
Step-by-step explanation:
The unit scale is a standard unit of measurement used to represent actual dimensions in a model or drawing. To calculate the unit scale for a frame size, you add the width and height of the frame together. For example, if the width of the frame is 4 inches and the height is 6 inches, the unit scale would be 10 inches (4 inches + 6 inches = 10 inches).