Answer:
78.5 cm
Step-by-step explanation:
C=2 X pi X r
r= radius
then divide by 2 for a half circle
since this is a multiplication, all the numerators are just factors of the product numerator and all denominators are just factors of the product denominator, so we can simply reorder them some, without changing the product.

Answer:
The answer is D.
Step-by-step explanation:
In similarity, the triangles have the same angles but different length of sides.
(Correct me if I am wrong)