Remarks to some of the exercises:
In b): You could use UPGMA, or just try to find a tree by informal reasoning.
Note: Exercises 9 and 11 are likely to be included in the compulsory assignment. Of course, nothing prevents you from having a look at them already. In particular, it is a good idea to have a brief look at the CLUSTALW program.
We can discuss the exercises on Monday, 30 January, but you should look at them yourself first.
Good luck!