How can I calculate work done when raising a mass using W = 32r^2?

[ElectronicTeaCup]

Homework Statement

A cable weighing 2 pounds per foot of length (and so having a mass of 2 pounds per foot) is
suspended from the top of a well 200 feet deep and extends to the bottom. Find the work done in
raising the cable to the surface. Over the distance of 200 feet you may use 32m as the constant
weight of a mass m.

Relevant Equations

$\frac {dW} {dr} = F$

Spoiler: Answer in solution booklet

Spoiler: Relevant section

I do not understand how to get $W = 32r^2$

 

[DrClaude]

I do not understand how to get $W = 32r^2$

Integrate $F$ over $r$.

 

[ElectronicTeaCup]

Awesome, thank you!