At work we somehow landed on the topic of how many holes a human has, which then evolved into a heated discussion on the classic question of how many holes does a straw have.
I think it’s two, but some people are convinced that it’s one, which I just don’t understand. What are your thoughts?
A regular straw has zero holes. The central cavity, through which beverages flow, is not part of the straw, and hence it’s endpoints are not holes in the straw.
A straw is topologically the same as a donut. It absolutely has one hole.