Answer = 150
Firstly, find out how many degrees the 12 sided regular polygon has using this equation:
(n stands for the number of sides)
(n - 2) x 180
(12 - 2) x 180
10 x 180 = 1800
Afterwards, divide the total amount of degrees in the polygon by the number of sides it has.
1800 / 12 = 150
Hope this helps :)
