Part a: hexagon is a six sided polygon.
Part b: dodecagon is a 12 sided polygon.
Part c: decagon is a 10 sided polygon.
Explanation:
Part a: The given polygon consists of 6 sides.
Hence, a polygon with 6 sides is called as hexagon.
Part b: The given polygon consists of 12 sides.
Hence, a polygon with 12 sides is called as dodecagon.
Part c: The given polygon consists of 10 sides.
Hence, a polygon with 10 sides is called as decagon.