1. On a segment graduated from 0 to 28 , a particle is at instant 0 at the abscissa point x0=10. At each instant, if it is at the abscissa point k=1.2,.27, it makes a jump of +1 with a probability k/28 or a jump of 1 with probability 1k/28. The process stops when the particle reaches one end of the segment. What is the probability that the process stops at the abscissa point 28