The task is to generate the correct answer for a given math problem.
--------
Question: Problem: the curved surface of a sphere is 64 π cm 2 . find its radius ?

Answer: 4', 'd ) 9', 'e ) 7'


Question: Problem: if sharon ' s weekly salary increased by 16 percent , she would earn $ 348 per week . if instead , her weekly salary were to increase by 15 percent , how much would she earn per week ?

Answer: $ 345


Question: Problem: in 10 years , a will be twice as old as b was 10 years ago . if a is now 9 years older than b , the present age of b is

Answer:
39 years