Access: Click the 
icon,
or Select Curves / Circle from
the main menu.
Create a Circle/Arc by picking 2 points through which the circle will pass and define its radius.
Required Step 1 
Pick the 1st point through which the circle will pass:
Pick the 2nd point through which the circle will pass:
Enter the radius of the Circle/Arc:
There are 2 possible solutions for Circle. The alternative solution is shown as a dotted line which can be picked for selection.
There are 4 possible solutions for Arc. The alternative solutions are shown as a dotted line which can be picked for selection.
Optional Step 1 
Pick a point to define the reference plane. (If no point is picked, the Circle/Arc is located on the XY plane of the active UCS).
If this is the final result, press OK
or Apply 
in the Feature
Guide to complete the function.
When completed, the Circle will appear in the Feature Tree as follows:
