4) Write an expression to find the sum of the measures of the interior angles for a concave polygon.
5) Explain whether the sum of the exterior angles of a concave polygon is equal to \(360^{\circ}\).
6) In a pentadecagon \(12\) of the angles add up \(2100^{\circ}\). Of the three remaining angles, two of the angles are complementary and two of the angles add up to \(170^{\circ}\). Determine the measures of all three angles.
5) Explain whether the sum of the exterior angles of a concave polygon is equal to \(360^{\circ}\).
6) In a pentadecagon \(12\) of the angles add up \(2100^{\circ}\). Of the three remaining angles, two of the angles are complementary and two of the angles add up to \(170^{\circ}\). Determine the measures of all three angles.