You are right. There are errors (mismatch) between UseCase diagram and the descriptive text.
I hoped they (SUN) would have recognized and accepted their mistake (with due appologies) and send an updated assginment.
Instead of wasting time getting them (SUN) to respond to the obvious mistakes, you can note down your assumptions, what you think is the correct requirements and submit the design. There is no way you can design with those mistakes in that requirement as it doesnt make any sense

[ December 05, 2007: Message edited by: Pranav Akshath ]