Financial Performance - Task 10, Costs

JohnPj

Hey guys, so i'm trying to study (but failing;() areas of task 10 on the FPFM exam. I have noticed in a practice assessment that when they ask to explain volume and contribution we have to do the highlow method etc.... Now, I did another practice assesment where it just said the basic explain the following expenses and how it affects gross profit margin.

I noticed that labour had gone up in cost (Production also went up) and the cost per unit had decreased , so I imagined it to be a semi variable cost and I did the high low method in my answer. When I checked my answer none of that was mentioned My question is , How do I know when its a Semi-Variable cost ? & Should I only calculate it when they ask to talk about volume and contribution ?

Been studying 2-3 hours a day on this and its wearing my down!!!! On the point of quitting