For the first question posted up.
If you look at the question, the time for each person indicates the distance of each person from the strike. From the first strike, you can make an estimate of where the first strike would have been. From there I would probably make an assumption that William is 3-4 seconds distance away from the strike.
For the 2nd strike, it got closer to Quentine but distanced itself from others meaning that the william got more distanced. Therefore, only reasonable answer can be D which is 4 seconds.