Isaiah sketches a model of a skateboard ramp. The model has two surfaces on which to skate, represented by sides AB and AD in the diagram. Triangle A B D is shown. A perpendicular bisector cuts angle B A D to form triangle A B C. Triangle A B C has angle measures 45, 45, and 90 degrees. Triangle A C D has angle measures 60, 30, and 90 degrees. The steepest side of the model, AB, measures 4 inches. What is the length of the other skating surface, AD? 2 StartRoot 2 EndRoot in. 2 StartRoot 3 EndRoot in. 4 StartRoot 2 EndRoot in. 4 StartRoot 3 EndRoot in.