TLDR: Unless you really want that 100k in liquidity, it's less hassle if you just pay it towards your student loans.
First of all, if you are 280k in debt by the time you graduate, the 100k you pay off would leave you with 180k principle. So taken into account, in 10 years of this is: 280k * (1.072)10=561120. If you pay off as much of your principle as you can now, that's 180k*(1.072)10=360720. The difference in interest here is 281k, vs 80k over 10 years or around 200k of which you would save if you pay it straight up.
Let's say you invest the 100k and you are in luck and you beat the 7.2 interest rate bench mark in the next 10 years. Let's assume you get 8.3 as your return. You get 221965.03 as your return or 121965.03 as your profit. You beat the bench mark 200k by a little, but after paying taxes, you're paying 15% (And that's on the low side in American history. Most of the time it's around the 20s) on those gains, which leaves you with 103770.28. For going through all of that you get only 3770 more if you pay now rather than you pay latter, but you still have to pay. At 190k starting salary after your residency, that's one weeks paycheck. Waiting 10 years with an unrealistically optimistic take of the business cycle, just to win a week's paycheck, is folly. So I wouldn't invest in your case just so you can beat the interest accrued on your loans, as there is a lot more risk than there is payoff.
Now if you attack your loan problem via PSLF, PAYE/IBR, you might be able to game the payments you pay back every month, but unless you follow through for 20-25 years, your principle is just going to grow and grow.
https://www.aamc.org/advocacy/meded/79048/student_loan_repayment.html
This is a quick reference:
http://members.aamc.org/eweb/upload/2015%20Debt%20Fact%20Card.pdf
Keep in mind here, your interest rates and principle are higher, so adjust accordingly.
If you have reliable transportation and you can relo yourself with little difficulty after graduation, I would pay most of that gift towards you loans.