What is the perimeter of a regular polygon with sides of length 15 cm and internal angles measuring 120° each?	Choose the correct choice from the following answers:
A) 90 cm  B) 108 cm  C) 120 cm  D) 132 cm  E) 144 cm
Sum of all interior angles is given by:   180(n-2) = n is number of sides   180(n-2) = 120*n   from here   n = 6   So perimeter becomes 15*6= 
<gadget id="calculator">15*6</gadget>
<output>90</output>
90   answer 90 cm
<result>A</result>
What is the perimeter of a regular polygon with sides of length 15 cm and internal angles measuring 120° each?