Answer:
infinitely fast
Explanation:
To have double the average speed, he must complete the two laps in the same amount of time that he spent completing the first lap. That is, he must complete the second lap in zero time.
Hamilton's average speed for the second lap should be infinite. (He needs to finish it in zero time.)
_____
speed = distance/time
Multiplying by 2, we get ...
2×speed = 2×distance/time . . . . . the time hasn't changed