I go over an introductory skills test for CNC Programming on Cartesian Coordinates. Do the work on your own, pause the video and watch the solution.
Link to the exam: https://drive.google.com/open?id=1KZRTLHbKfIt78Fv0mn5yE1T-DJkWczZ2cwusX2DyFDc
Good resources: https://www.amazon.com/shop/colfaxmath (paid link)