To rotate dimension text

Advanced experience level

Do one of the following:

Choose Insert > Dimensions > Rotate Dimension Text.
On the Dimensioning toolbar, click the Rotate Dimension Text tool ().
Type dimedit, press Enter, and then in the prompt box, choose Rotate Text.

Type the new dimension text angle, and then press Enter.
Select the dimension to be rotated, and then press Enter.

Select the dimension to be rotated (A), and then type the rotation angle.

Result.