At those capacities and charging times there's no chance of it not being some medium voltage (4160v or higher) equipment. Even a 480v 3ph low voltage building power system wouldn't be realistic because a single charger would be more than double the service size as the entire remainder of the gas station. However it would be done this would need a massive upgrade in electrical that isn't going to be available at your neighborhoo station. Also raises some safety and logistics concerns, you can't trust the average person with that degree of potential hazard.
Exams are for testing ability to learn that knowledge. If/when you need that knowledge you have a starting point for how and where to obtain the necessary information again.
I think I'd have to go with RC Bray. I could listen to him tell me just about anything.
Desktop - Kbin. Android - Lemmy. Mobile apps for Lemmy instances are far more function than the mobile site for kbin.
This isn't the only property that makes mental math easy. What is 3.5% of 62? Inverting the percentages doesn't really help but if we realized 3.5% = 1%+1%+1%+0.5% we have some easy math. This gives us 0.62+0.62+0.62+0.62/2=2.17
Also remember there isn't a teacher sitting over your shoulder to check your work, most of the time you do mental math, getting close is good enough. 62 is close to 60 and 3.5% is close to 4, and 60 x 4% is easy math to get an answer that will be a little less than 2.4.