The interior angles of a simple (and planar) quadrilateral ABCD add up to 360 degrees of arc, that is. This is a special case of the n-gon interior angle sum formula (n â 2) Ã 180Â°. All convex quadrilaterals tile the plane by repeated rotation around the midpoints of their edges.
1 CostHelper readers report paying $150-$300 for a windshield replacement, at an average cost of $214. 2  WindshieldsToGo.com provides an online form to estimate the cost of windshield replacement with and without installation, based on zip code and the year, make, model and style of vehicle.
1 Comprehensive auto insurance often covers windshield replacement, either with a $100-$300 deductible or with no deductible amount due, according to the Insurance Information Institute.2  Windshield repair or replacement is typically done by a shop or mobile service specializing in auto glass work. If the vehicle has windshield wipers attached to the windshield, these wipers will need to be replaced at an average cost of $7-$20 each.