In model space (MODEL), a room label text height is set to 300 mm in...

the formula for determining object scaling is:

Object Height x Annotation Scale x Annotation Plot Size = Model Space or Paper Space Height

In this case, we want the room label text height to be 3 mm in paper space when plotting the drawing. Assuming an annotation plot size of 1 mm and an object height of 300 mm, we can solve for the annotation scale as follows:

300 x Annotation Scale x 1 = 3 Annotation Scale = 3 / 300 Annotation Scale = 0.01

Therefore, the viewport scale that corresponds to this annotation scale is B. 100:1.

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