It does not say "approximately" - sorry about that. I assumed it did. I guess that saying to a student "approximately" would imply that _any_ answer is correct since "approximately" could be interpreted many ways - and in student lingo if they are given a mm they will usually take a km! I think the project still is a neat one and one that should make them think. Which is good from the instructor's pov but not necessarily that of the student! asta, andy
