Not sure what the minimum is as I do not want to spend too much time writing
My teacher always says write at least a page and a quarter, if you can write more and you have time though, you should! She corrects the exams every year and says that examiners are looking for 8 SRF's ( Significant Relevant Facts) BUT she advices to always put in 10 as you don't know which facts the examiner will accept. As long as you have the 8/10 the length shouldn't really matter as much!
it doesn't matter how long the essay is as long as it has 8/10 SRF's it doesn't matter.My teacher always says put down at least 10 SRF's.You don't get marked on how long the essay is only what related to the topic begin asked!
my teacher wants 20 SRFs but it depends on the length of the history essay or what you're doing. the topic i'm doing there is at least 20 SRFs so yeah