In this task, you need to answer the given multiple-choice question on geometry. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

[Q]: Problem: it has been raining at the rate of 5 centimeters per hour . if the rain filled a cylindrical drum with a depth of 15 centimeters , and area 300 square centimeters , how long did it take to fill the drum completely ?
Options: ['a ) 3 hours', 'b ) 4 hours 15 minutes', 'c ) 6 hours', 'd ) 2 hours 5 minutes', 'e ) 8 hours']
[A]: a

[Q]: Problem: if the area of a circle is 16 pi square feet , find its circumference .
Options: a ) 8 pi feet , b ) 28 pi feet , c ) 38 pi feet , d ) 48 pi feet , e ) 58 pi feet
[A]: a

[Q]: Problem: the volume of a sphere with radius r is ( 4 / 3 ) * pi * r ^ 3 and the surface area is 4 * pi * r ^ 3 . if a sperical balloon has a volume of 2304 pi cubic centimeters , what is hte surface area of the balloon in square centimeters ?
Options: ['a ) a . 40', 'b ) b . 100', 'c ) c . 400', 'd ) d . 1,800', 'e ) e . 10,000']
[A]:
d