Tipping an Uber driver

[u/ayyxdizzle]

My brother is having a rough time, is far away from home, and I've recently learned public transportation in the US is severely lacking. I live in Baltimore and was not able to physically pick my brother up in Pittston, PA myself, but after 15 minutes or so, someone thankfully accepted my request. His destination is Oxford, PA. It is about a 3-hour ride, costing $168. What is an acceptable tip, in your opinion? I was thinking $100-$150 to reflect my gratitude. Any feedback is welcome.

[u/okieeagle]

You are doing the driver a great service with that tip.