The Offside Rule in Soccer - Solution

1. E
2. G
3. In Mark's frame of reference, B is simultaneous with E. Since Mark entered the offside position at F which is before E, it was before the ball was kicked.
4. In John's frame of reference, B is simultaneous with G. Since Mark entered the offside position at F which is after G, it was after the ball was kicked.
5. Light from B reaches Luke at I. Light from F reaches Luke at K. Since K happens before I, Luke sees Mark enter the offside position first, and then the ball being kicked by Matthew.