Step-by-step explanation:
what I don't understand is why the distance around the window has to be written twice.
but let's start with the circumference of the complete circle :
2×pi×r = 2×22/7 × 3.5
or as the boxes are lined
22/7 × 2 × 3.5 = 22/7 × 7 = 22 ft
the circumference of half the circle is then about
22/2 = 11 ft
the distance around the window is then
11 + 3.5×2 = 11 + 7 = 18 ft
