Respuesta :

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 =