Because a circle has a constant diameter. The cover of the man hole won't fall down in anyway Unlike, if it's a square, the cover could still fall because a diagonal drawn in a square is longer than its sides.
There are various reasons that manholes are shaped like a circle. For example, it is much easier to dig a circular hole.
No state in the US has all of their manhole covers shaped like Oreos.
A wedge shaped portion of a circle is called a sector.
A circle has to be ring shaped (starting and finishing at the same point) otherwise it isn't a circle.
Because they are meant for a man to go through them
There are approximately 100,000 manholes in Manhattan.
Did you know that the sun is circle shaped?
Manholes are human access points for when the sewer system needs maintenance or repair.
None, but we have a couple square-shaped.
"Circular", meaning shaped like a circle.
a "Flat circle thing that's flat" ;)
it was a circle