The arithmetic that carries the numerical marks, worked step by step.
Use unit cancellation by arranging conversion factors so unwanted units cancel and the unit you need remains. Calculate with the full values, then round only as the question instructs.
ResourceHere is a free PDF, no sign-up. It is the sheet you would write out the night before. Then, further down, the straight answer about the code itself.
PracticeMost people fail the calculations and the judgement questions, not the recall. Here is what the real ones look like, and ten you can sit right now.