Answer
30$^{\circ}$
Work Step by Step
E=$\frac{360}{n}$
E=$\frac{360}{12}$
E=30$^{\circ}$
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.