No. Zachary should have drawn the first two arcs with the compass centered at B.

Yes. Zachary correctly constructed the median from C to AB¯¯¯¯¯¯¯¯.

No. Zachary should have drawn the second pair of arcs using a different compass width.

Yes. Zachary correctly constructed the median from A to CD¯¯¯¯¯¯¯¯.