When a circle rolls around the outside of another circle it will rotate by a certain angle. For these problems the fixed circle will have radius r. Given the following conditions, by how many degrees will the moving circle rotate if it rolls around the fixed circle once?
a. Assume the rotating circle has radius r (shown).
b. Assume the rotating circle has radius 12r.
c. Assume the rotating circle has radius 2r.
d. Assume the rotating circle has radius 13r.