$\"\"$

Radius of the layer is $\"\"$ .

Volume of the disk is $\"\"$ .

The water weights $\"\"$ .

Distance the disk of the water moved is $\"\"$ .

Weight of the layer is $\"\"$ .

The weight of the layer is $\"\"$ .

$\"\"$

Calculate the work done in filling the tank half full of water through a hole in the bottom using

water from the stream:

$\"\"$

Apply integration:

$\"\"$

The work done in filling the tank half full of water through a hole in the bottom using

water from the stream is $\"\"$ .