Puzzle thread? Puzzle thread.

[tommo]

First one. Spoiler for ewrwe: No, I don't think so. If I start at one edge and run to the other (maximising the distance he must go, while also minimising the distance I must go), say it is 10m diameter. He will have to go (c= pi X d)/2 which is 15.7m and I will go 10m, obviously. At 1m p/s it will take me 10 seconds to get to the other side. At 4m p/s it will take him 3.9 seconds.