How hard is 75 WAM engineering?

hello gonna look at starting civil or electrical engineering in uni soon. Just wondering how hard it is to maintain a decent WAM? my sweet spot wam target is around 75 to 80 and I’m just wondering how hard 75 at a minimum is to get especially for electrical. how much study a day do I need to do outside of uni classes? even keeping at 75 low distinction is fine with me? but how hard is it?