Service costing

See my reply to your previous post - do not simply set me questions!

There is no specific method. Efficiency is looking at how well the company is using their resources. So in this question you would look at the cost per unit sold to see which was the more efficient (the lower cost per unit, the better).

Your question on target costing cannot be asked in the exam - in Paper F2 you cannot be asked calculations on target costing. However, even then, the question as you have typed it is impossible to answer. It is needed to know on what the return of 20% is to be calculated. Are you sure it says return, and not mark-up or margin?