I'm from a Cambridge background, not Oxford, but the trick to this sort of essay is that the journey is the destination. That is, ultimately it's not expecting you to reach a single right conclusion, but to present evidence, argument, and references.
The rubric doesn't say, but I'm guessing you'd get three hours per essay, one hour per question, minus the minutes spent selecting which ones.
Of course, but I am wondering if you wrote a brilliant essay arguing for a viewpoint that seems to go against the one underlying the selection of questions here, would it matter?
My guess is no, it wouldn’t. These questions all have pretty strong assumptions behind them, and so my guess is that they’re looking for people who fundamentally have the same opinions but are capable of communicating them well. And not someone that has different opinions, even if they communicate them well.