Answer:
18.9cm ( I rounded of and used Π as 3.14)
Step-by-step explanation:
P=distance all round
=1\2ΠD +Πd
see you have to calculate the upper length of the circle , since its half u multiply by a half. And since its not fully shaded the two semi circles are now included as the lower part of the whole shape. so you add them too. (I hope I'm making sense)
