Analysis:?

Translate a and e upward, and the length of a whole side is12 cm; ; Translate B to the left, and the length of an entire side is 9cm. At this point, the perimeter of the figure is the perimeter of the whole rectangle. Adding the lengths of two sides (both 3cm) of C and D, the circumference of the graph is 2* 12+2*9+2*3=48(cm).