Expected standard
Stonehenge is in England, not Ireland. It depends what you mean by 'answer', since Stonehenge was built and altered over a periopd of about 1,500 years, with different purposes at different times. Stone circles and other stone monuments were erected in many parts of the Celtic world including Britain, Ireland and northern France.
A short run is a periopd of time in which some factors of production(machinery,building,technical labour)can't be changed due to insufficiency of time while others like(raw material,ordinary labour,power etc.)can be changedaccording to the output to be produced.