Please answer this question now

You are assembling pieces of an iron gate to complete a fence. the finished gate will look like the one below. in order to assemble the gate it is important to under how the pieces are related. part 1: how are pies 1 and 2 in the archway related? part 2: how are the rectangular sections 5 and 6 in the center of the gate related to each other?

Gh bisects fgi. find the measure of hgi •15° •21° •10° •8°

How many sides does a regular polygon have if each exterior angle measure is 45 degrees explain your answer, i really don't understand this.