Heptagon Angle Theorems

Interact with the applet below for a few minutes.   Then, answer the questions that follow.   Be sure to change the locations of the heptagon's BIG BLACK VERTICES each time before you drag the slider!!! Note: Each point on a side of this heptagon is a midpoint.
Questions: 1) What geometric transformations took place in the applet above?   2) When working with the heptagon's interior angles, did any of these transformations change the measures of these interior angles?   3) From your observations, what is the sum of the measures of the interior angles of     any heptagon?   4) When working with the heptagon's exterior angles, did any of these transformations change the measures of these exterior angles? 5) From your observations, what is the sum of the measures of the exterior angles of     any heptagon?