?Help please

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

The triangle shown has a hypotenuse with a length of 13 feet. the measure of angle a is 20 degrees. and the measure of angle b is 70 degrees. which of the following is closest to the length, in feet, of line segment ac? no need to use a calculator to find the trig numbers. each function is listed below. 4.4 5 12.2 35.7

How is this equation completed? i cannot find any examples in the book.