PLS PLS HURRY!!!! 50 points!!

Fred and Ted are racing cars down a frictionless track with a jump at the bottom
when suddenly an argument breaks out. Fred says, “If we release the cars from a
point twice as high as we are currently doing so, the cars will have twice the
gravitational potential energy, and therefore be travelling twice fast when they hit
the jump." Ted says, “In order to double the speed of the cars when they hit the
ramp, I think we will have to more than double the height!" Who is right? Prove it!