In this task the focus is on physical knowledge about the world. Given the provided goal task in the input, describe a process that would lead to the asked outcome. This process often involves physical motions with objects, such as moving them, arranging them in a certain way, mixing them, shaking them, etc. 

plug
can be used to stop a drain

How to ensure the scale for the room layout is to size?
Use a calculator to properly work out the dimensions to the smaller scale

Clean gunk from pools.

Float a few tennis balls on the surface.