**1. The problem statement, all variables and given/known data**

Problem is attached

**2. Relevant equations**

A formula sheet is also attached

**3. The attempt at a solution**

flux=[itex]\int[/itex]B dA from .31m to .82

B=u I(enclosed)/2(pi)(d)

d=x

dA=dx L

so ∫ (u)(I)(L)dx / 2(pi)(x) from .31m to .82m remember x=d in the pic. My answer is 3.9687e-7 and its wrong

integral came out to be (u)(I)(L)/2pi (ln(.82) – ln(.31))

u=4(pi)e-7

I=4A

http://ift.tt/1f8yBky