Contractions in GCSE English, History, etc.?

Are contractions allowed in exams such as WJEC GCSE English Language and AQA GCSE History?

WJEC GCSE English Language includes a reading exam and a writing exam (which consists of questions such as writing formal letters, writing informal letters, writing articles or writing film/book/video game reviews).

If you believe that the use of contractions would differ in suitability across these tasks, then please do specify. Please also specify whether you think that all contractions should be allowed, only some (and which those are), or none at all.

I don't do your exam board for English Language or take history but I would say in general try to avoid contractions.
You can probably use them in informal letters but in any type of formal writing you shouldn't be using them. I wasn't allowed to use them in my English coursework for the film review and formal letter I did.
For history essays, I can't be sure but avoid them just to be safe