How do you get black skid that wont come off marks from a bike tire off a concrete driveway?

Okay so one day i was messing around with my friends bike and i was skidding on my friends drive way with a trek bike. The skid marks were left on concrete and he has sprayed them with water using his thumb and a hose. He said he even scrubbed them and they wont come off. My question is how do you get black skid marks from a bike tire off a concrete drive way? Is there products or devices that are cheap that i can use to remove the marks?