[BUG] The Valley

[Tevian Dray]

> Just a minor point:  In problem number 2 students are asked to choose a
> curve.  In problem 3 they are asked to evaluate a line integral along
> the curve C.  However, C was never defined!
> 
> If this lab is to be done as a way to introduce line integrals (as I'm
> planning), it should probably be made explicit that the curve chosen in
> problem 2 is in fact C.  

Good point.  This raises an interesting question of notation: Why not omit
the C altogether?  The integral in problem 3 is clearly a line integral, and
the problem specifies the location in words.  So why does it feel wrong to
leave the limits out?  Especially when each group will choose a different
curve, all of which are being called C.

Tevian