The surface area of a sphere is same as the curved surface area of a right circular cylinder whose height and diameter are 6 cm each. The radius of the sphere is  Choose the correct choice from the following answers:
A) 3 cm
B) 4 cm
C) 6 cm
D) 8 cm
E) none

Rationale: "solution 4 î r 2 = 2 î 3 x 6 â ‡ ’ r 2 = ( 3 x 6 / 2 ) â ‡ ’ 9 â ‡ ’ r = 3 cm . answer a"
Answer: A