TASK DEFINITION: You need to answer a given question containing a blank (_). Your answer must be one of the two objects mentioned in the question, for example "trophy" and "suitcase". Your answer must not contain a word that is not present in the question. Please don't use articles (e.g., the, a) before the answer.
PROBLEM: The professor preferred to teach with the books instead of the computers, because the _ were out of date.

SOLUTION: computers

PROBLEM: The chocolate could not be sliced with the knife because the _ it too blunt.

SOLUTION: knife

PROBLEM: Camille and Ryan tried to create a plan that worked around their schedules for their custody agreement, but it didn't work out because the _ was difficult.

SOLUTION:
plan