[填空题]
The table below shows (cpl3u,hs j;3q 2hoqy j1qkc,the costs, in euros, of the dir p77qgf4)o d,ha)i59zljn3kdh8sbjos k m 9e1ect bus rides between six towns (A-F). Cells with dashes indicate that there are no direct bus rides between the two town7isz)d bkhjeagh8ms3 9)19,7 o 5okdfnj pl4qs.
1. Draw a weighted graph showing the direct bus rides between the towns and their costs.
2. (1) Write down the adjacency matrix for the graph of direct bus rides between the towns.
(2) Hence find the number of different ways to travel from and return to town F in exactly 6 bus rides.
3. State whether it is possible to travel from and return to town \mathrm{F} in exactly 6 bus rides, having visited each of the other 5 towns exactly once.
The following table shows the minimum cost to travel between the six towns. A travelling salesman wants to visit each of the six towns, starting and finishing at town F.
4. Find the value of p and the value of q .p = q =
5. Use the nearest-neighbour algorithm to find an upper bound for the cost of the travelling salesman's trip. euros
6. By deleting vertex F , use the method of vertex deletion to find a lower bound for the cost of the travelling salesman's trip. euros
