For this case we have that the area of a regular polygon is given by:
[tex]A = \frac {P * a} {2}[/tex]
Where:
P: It is the perimeter
a: It is the apothem
Since we have a dodecagon, then the perimeter is:
[tex]P = 9 * 12\\P = 108 \ cm ^ 2[/tex]
Then, the area is:
[tex]A = \frac {108 * 16.8} {2}\\A = 907.2 \ cm ^ 2[/tex]
ANswer:
Option B
