I believe 2 (226.1 mm) is the correct answer.
Step 1.
Find the circumference of the circle.
6(2)•3.14
37.68
Step 2. Multiply the circumference with the height (12mm)
37.68•12=452.16.
Final step: Divide your final answer by 2 because this object shown above is a cone.
452.16/2=226.08
