$\"\"$

length of the chain is $\"\"$ ft.

Weight of the chain is $\"\"$ lb.

Weight of the chain per unit length is $\"\"$ lb/ft.

If a small pice of chain is at a height $\"\"$ , it moves from $\"\"$ to $\"\"$ then

Distance function is $\"\"$ ft.

Work done as a Riemann sum is $\"\"$ .

$\"\"$

$\"\"$ lb-ft.

$\"\"$

Work done required to lift the chain is $\"\"$ lb-ft.