The analytical formula of 2.2. The CD is: Y=-9/20X+37. If you arrive on time and X=740/9, the total time is 740/9+5=785/9.
3, (6-1)/(80-18) = 5/62 This is the speed of B, (10- 1)/5/62=558/5, which is the second time that B meets A.