[问答题]
A package delivery company offers 24 hours delivery ser
k6vue4u-hr /lvice to a limit
*;a *ig r3efjjx 8h,hw3lg2a3 0lv5yzl3h wayed number of cities in close proximity. The directed graph below shows four cities served (A-D) and the routes of delivery between th
;g,3j3x wlvli3ahaz0y r*w* 3ajhey h2l58 fgem.
1. Find an adjacency matrix $\boldsymbol{A}$ for the shipping network.
2. Find the number of ways it is possible to ship a package from city $\mathrm{C}$ to city $\mathrm{A}$ using exactly three delivery routes.
3. (1) Find the matrix $\boldsymbol{S}_{3}$ , where $\boldsymbol{S}_{3}=\sum_{i=1}^{3} \boldsymbol{A}^{i}$ .
(2) Hence write down the number of ways it is possible to deliver a package from city A to city D using three or less delivery routes.
(3)State all possible ways to ship a package from city A to city D using three or less delivery routes.
