#8: By definition, alternate exterior angles are angles on opposite sides of the outside of the lines that are congruent to each other. For this question, this could be represented by angles 1 and 8 and angles 5 and 4.
#6 If we know that ABC is a right triangle, then we know that one of the angles (the right angle) is 90 degrees. We also know that another angle is 40 degrees as shown in the picture. If all triangles add up to 180 degrees, then we know that the missing angle is 50 degrees. Based on the placement of angle ECD, we can add up the two sides of the triangle furthest away from angle ECD (90+40=130) so angle ECD equals 130 degrees.