Notes to answers

That depends on what you mean by notes and what is the specific requirement of the question. If a question states to “calculate” or “compute” then you do not require explanations for your calculations, but what you always require (section B) is workings to show where the numbers included in your answer come from!
This is something that at the end of your studies you will be able to experience when you attempt the updated past exam questions in an exam kit/revision kit from one of the approved providers.