Please Help I will Give Brainest and 100 points and no fake answers

Points a, b, and c form a triangle. complete the statements to prove that the sum of the interior angles of triangle abc is 180

In the following diagram it is given that dec, ab || dc, ad || eb, and ad is congruent to bc. a)why isn't abc a parallelogram even though it has a pair of parallel sides and a pair of congruent sides b)explain why be must be congruent to bc. further explain what type of triangle this makes triangle abc and what it tells you about angle 1 and angle 2c) finally why must angle 3 be congruent to angle 1? further, explain why we know that angle 3 is congruent to angle 2

If you answer 2+2 you will get over 80 points