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oops

Well, I'm going to spend an infinite amount of time traveling the first 500m. Therefore, my speed will be approaching 0m/h. If I maintain that speed, I will also travel the second 500m in forever. But forever twice is still just forever, so I have effectively doubled my speed, just like you wanted me to.

interesting appraoch :)
but I cannot agree with x=2x while x tends to infinity
although they are both infinity, but algerbarically they are bot approaching each other