In future, if you want me to answer then you must ask in the Ask the Tutor Forum – this forum is for students to help each other.
Other overheads are apportioned on the basis of labour hours (which is what the question asks for) and so it is necessary to calculate the total labour hours worked (units x hours per unit).
Have you watched the free lecture on ABC, because the test question is very very similar to the example that I work through in the lecture? (and there is no point in using the notes without watching the lectures – they are only lecture notes and it is in the lectures that I explain and expand on the notes.)