The first question is AB=3K and AD=5K. Because AE bisects the angle BAD and AB=BE=3K, EC=2K=4 and K=2.

So AB=6, AD= 10, and the circumference is 32.

Question 2: Because CE is parallel to AD and AO=OC, it can be proved that triangle AOD and triangle COE are congruent. So DO=OE is obtained, so the quadrilateral ADCE is a parallelogram, so AD and EC are parallel and equal.