Charlotte the turtle was born with 4 squares on her shell, as in the first picture below. When she was 1 year old, 12
new squares appeared around the old squares, as in the
second picture below. Each year, a new group of squares
appeared around the old squares.

“exterior angles of triangles. an exterior (or external) angle is the angle between one side of a triangle and the extension of an adjacent side. try this drag the orange dots on any vertex to reshape the triangle.” look to get to the answer i explained what it means and other things i hope it you .