If circles x and y have the same area and circle x has a circumference of 20π, half of the radius of circle y is:	Pick:
A) 16  B) 5  C) 4  D) 2  E) 1

Rationale: "x b é radius of circle x ý b é radius of circle y given : pi * x ^ 2 = pi * ý ^ 2 also , 2 * pi * x = 20 * pi x = 10 thus ý = 10 y / 2 = 5 ans : b"
Answer: B