I'm new to SW and just started working through the practice CSWA exam. I'm trying to draw the part given in the first part of the practice exam, but I'm unfamilar with one of the (constraint?) symbols shown:

I'm referring to the symbol showing a circle touching the edge of a straight line. What does it indicate?

Here's my drawing thus far:

I think I'm close, but my 3-point arcs don't look correct to me and I'm thinking it's because I didn't do whatever those symbols indicate. File attached.

Thanks for your help!