Exterior angle measures 18 degrees Interior angle measures 162 degrees
Providing that it's a regular polygon then its interior angles will add up to 1260 degrees with each of its 9 interior angles measuring 140 degrees.
Each exterior angle measures 20 degrees Each interior angle measures 160 degrees
Providing that it is a regular hexagon then the each interior angle measures 120 degrees and each exterior angle measures 60 degrees
Interior angle = 120 degrees Exterior angle = 60 degrees
Subtract the interior angle by 360 degrees
Each interior angle measures 150 degrees Each exterior angle measures 30 degrees
Providing that it is a regular nonagon then each exterior angle measures 40 degrees and each interior angle measures 140 degrees