look at the shaded figure. what is its perimeter? units

look at the shaded figure. what is its perimeter? units
Answer
Explanation:
Step1: Contar lados exteriores
Contamos los lados exteriores de la figura sombreada.
Step2: Sumar los lados
Cada lado mide 1 unidad. Al contar, vemos que hay 18 lados exteriores.
Answer:
18