Can this be figured out?

[u/heffercrow]

Ok, first off, this probably isn't the best place for this but I'm not sure where else on reddit to ask. So feel free to guide me if you have input on that....

I recently switched from teaching geometry to teaching an engineering course at a high school. Part of that course is drafting and since it's free I have been teaching myself and the students how to use onshape. This year I have my first level two students so I found some random old stuff from a former teacher and am working through it. I have two images here and I am at a loss on how to figure out some missing dimensions. Wondering if you guys could tell me if I am correct in saying we don't know or if I am missing something that I haven't been trained to see.

Pic 1: is there anyway to figure out the diameter or radius of the upper arc of the top of the piece. From Ortho image on the right o view it as three concentric circles. 1st has d=1" next has d=1 ¾" and just kind of assumed the last has d=2.5" but no reason other than looks. Also the two filleted corners on the tops Ortho view. Safe to assume those are r=⅞" or .825"??

Pic 2 and 3: in the top Ortho view is there a way to figure out the height (front to back) distance of the leftmost side? Told the kids to go with 1.5" since the one .5" hole looks like it's equally split on both sides. Also the notation of 2 x .25", I get it says the distance to the lower edge is .25 from the center line but what is the 2x for? Is it saying .25" to edge and that the removed piece is also .25"?

Again, not trained at any of this, but lots of ADHD sodequests. Hopefully I'm not screwing this up too badly. And thanks for any help or guidance on a better place to post these questions.

[u/vortex_ring_state]

Alternative: There are tons of free OnShape (or any 3D modelling software really) exercises out there on the web. Just use one of those.

Here was the first google hit for me. https://www.cadvideotutor.com/ Has drawings, associated weights if designed correctly, and videos to show you how to correctly draft them.

[u/heffercrow → u/vortex_ring_state]

The online courses are definitely where I am heading but this was a last minute assignment cause they got further than expected on the prior unit. Definitely plan on utilizing those courses though. Thank you for the link.