Hey, i have 14.5k total in student loans left at 4.2%, 3.8%, and 3.4% interest. My plan is to pay these off as slow as possible since after deducting interest from taxes (25% marginal bracket) I would almost certainly get more from investments over a 10 yr period. If you were to refinance your student loans to a lower rate, is the interest still deductible from taxes or is it only from federal loans? Also, would i realistically be able to get a lower rate if i refinance all of these loans into one? The geometric mean of the interest rates is 3.65% and after deducting right now the geometric mean would be 2.73% so is it possible to refinance to lower than this?

Thanks!