What if your Primary Research Interest is Sales Management?

I'll give you a full week as I don't think there's such a thing as a typical day.

The actual schedule depends on a bunch of things, and early on heavily depend on how many courses you have and what these courses are like. About half of my coursework has been Economics courses (Microeconomics, Econometrics, Contract Theory, Game Theory, the like) while the other half have been Finance and Accounting seminars. The econ courses were usually lighter on reading but heavier on problem sets ("Prove or disprove the following: demand can be written as a function of aggregate wealth if and only if preferences are homothetic"). This means a pretty variable load over time, but if you take the hardest undergrad course you ever had and multiply the time spent by 1.5 this is pretty much it.

On the other hand, field seminars are usually much more time-consuming because you read many journal articles (anywhere from 2 to 6 per week per course, articles are usually from 15 to 40 pages long). Most of the seminars I attended had student presentations, so you can expect to have to present a few articles per course, whether on an informal basis (ie. present the intuition and that's it) or a more formal way (powerpoint, dive into the proofs, make a numerical example, present a possible extension, etc.) To this you add the weekly (or so) workshops where you read yet another article and sometimes meet privately with the (guest) speaker to discuss his own research.

In all, I'd say the first semesters were harder because the course load was more intensive, there was a lot to read, and the math was just at a much different level than I'd ever been exposed to, so I spent every day, most evenings and some weekends on coursework. Lately my coursework has been lighter so I usually don't work at night (and hang out on forums like this one) and I usually have at least Saturday PM and Sundays off.