Which of the following is true?
- If an action has a given literal as a precondition and another action
has the negation of this literal as a precondition then there is a
Competing Needs mutex between these two actions.
- We called the OO-like ontology that made use of Is-A/subclass relationships
a Lower Ontology.
- The Ignore Preconditions Planning Heuristic removes all the delete lists
from the effects of all actions.