如图，在四边形ABCD中，E,F分别是边CD,AB上的点，连结EF, 过点E作NE⊥DA,垂足为N.已知∠A=∠C,∠1=∠2. （1）说明AD//BC的理由； （2）说明NE⊥BC的理由.---**Question Stem:** As shown in the figure, in quadrilateral ABCD, E and F are points on sides CD and AB respectively. Connect EF. Draw NE perpendicular to DA from point E, with N as the foot of the perpendicular. Given ∠A = ∠C, ∠1 = ∠2. **(1)** Explain the reason for AD // BC. **(2)** Explain the reason for NE ⊥ BC. --- **Chart/Diagram Description:** * **Type:** Geometric figure, specifically a quadrilateral with internal lines and a perpendicular segment. * **Main Elements:** * **Quadrilateral:** ABCD, with vertices labeled A (top-left), B (bottom-left), C (bottom-right), D (top-right). * **Points:** * A, B, C, D are vertices of the quadrilateral. * E is a point on side CD. * F is a point on side AB. * N is a point on side AD. * **Lines/Segments:** * Sides of the quadrilateral: AB, BC, CD, DA. * Internal segment connecting F and E: EF. * Internal segment connecting E and N: NE. * **Angles:** * An angle labeled '1' is located at vertex F, appearing to be ∠AFE. * An angle labeled '2' is located at vertex E, appearing to be ∠DEF. * A right angle symbol is shown at point N, indicating that segment NE is perpendicular to segment DA (∠END or ∠ENA is 90 degrees). * **Relative Positions:** * F is on segment AB. * E is on segment CD. * N is on segment AD. * Segment EF connects F on AB to E on CD. * Segment NE is drawn from E to AD, forming a right angle at N.