Detailed modeling

I am still having some challenges how to position and model with exact measures. This is probably because I have been modeling so long with other 3D modeling tool. What would be your workflow when modeling these 2 cases? See examples from Shapr3D intro video and pictures below.

  1. How would you make sure that these 2 lines are drawn parallel and the same distance (for example 50mm) from the center line of the circle?
    A

  2. How would you position the circle (cut) in the center of the face?
    B

Thanks for these explanations/videos this helps a lot! It seems that in Shapr3D you need to use lines and offsetting lines to replace construction lines in Sketchup. Anyway, it would be great to have Sketchup’s add center point plugin functionality in Shaprt3d. That would save a lot of time because it seems that in Shapr3D you can only identify center points when working with sketches.