com.umlet.element.base.Relation3605040120lt=<().20;20;20;100com.umlet.element.base.Relation2403023054lt=<. <<extends>>20;34;210;34com.umlet.element.base.UseCase2020240100select flight -- extension Points availability check: flight is fullcom.umlet.element.base.UseCase4504019050determine alternativecom.umlet.element.custom.AlternativeUseCase3013026080select flight -- extension points availability check: flight is fullcom.umlet.element.base.Note37015025050Condition: {flight is full} extension point: availability check