Which of the following statements are true? Select all that apply. There are two horizontal parallel lines are cut by a transversal. The top left angle is denoted by 1 when transversal line makes an angle with upper horizontal line. The supplementary angle of angle 1 (which is top right angle) is denoted by 2 and opposite angle is denoted by 4. The remaining angle is denoted by 3. The corresponding angle of 1 is denoted by 5 and the corresponding angle of 2 is denoted by 6. The opposite angle of 5 is denoted by 8 and opposite angle of 6 denoted by 7.

A. ∠3 ≅ ∠2 because they are alternate interior angles.
B. m∠1 + m∠3 = 180° because they form a straight angle.
C. ∠3 ≅ ∠6 because they are alternate interior angles.
D. ∠1 and ∠6 are supplementary because ∠3 ≅ ∠6 and m∠1 + m∠3 = 180°.