Answer:
(21 ft)(π/2) + 21 ft
Step-by-step explanation:
Here the diameter of the semicircle is 21 ft.
πd
Half of the circumference of the full circle with diameter 21 ft is C = ---------
2
so if d = 21 ft, that half circumference is πd/2.
To this add the diameter (the horizontal line defining the bottom of the
figure): πd/2 + d = (21 ft)(π/2) + 21 ft.
Perimeter of this semicircle is P =