there is sky lost at the calculator and the curing perimeter
displaced_threshold_runway is flat_terrain. connectedness_preserving_projection is surface_projection. azimuthal_projection is surface_projection. connectedness_preserving_projection is dimension_preserving_projection. production_possibilities_frontier is two_dimensional_cartesian_graph. overlap_preserving_projection is surface_projection. parts_preserving_projection is surface_projection. dimension_preserving_projection is surface_projection. overlap_preserving_projection is connectedness_preserving_projection. runway_touchdown_zone is object_surface.