Understanding Exercise c: Is the Flux Q an Integral?

[dirk_mec1]

Homework Statement

http://img528.imageshack.us/img528/3623/47021164uu2.png

http://img18.imageshack.us/img18/8634/21260108gr1.png

The Attempt at a Solution

I have a question about exercise c. The flux Q is the integral, isn't it? So why do they use the word "then"?

 

[dirk_mec1]

I think that the question isn't correctly posed. I think it should be like this:

"Calculate the flux Q through the slit... width in other words evalute the integral".

Is this correct?