Creating arc segment

Newby here. I need to create a pair of 20" radius arc segments with center points, x0y2 and x0y-2 and 2 lines parallel to y at 1.687 and -1.687.  Also another pair of lines at y.875 and y-.875. I'm used to working from an origin point and Cartesian coordinates. Help! TIA

Hello and welcome!

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