TASK DEFINITION: In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.
PROBLEM: Problem: find √ ? / 19 = 4 ? 
Options: a ) 76 , b ) 5776 , c ) 304 , d ) 1296 , e ) none

SOLUTION: b

PROBLEM: Problem: you and your friend spent a total of $ 19 for lunch . your friend spent $ 3 more than you . how much did your friend spend on their lunch ? 
Options: a ) $ 9 , b ) $ 3 , c ) $ 4 , d ) $ 6 , e ) $ 11

SOLUTION: e

PROBLEM: Problem: if grapes are 91 % water and raisins are 19 % water , then how many kilograms did a quantity of raisins , which currently weighs 9 kilograms , weigh when all the raisins were grapes ? ( assume that the only difference between their raisin - weight and their grape - weight is water that evaporated during their transformation . ) 
Options: a ) 63 , b ) 72 , c ) 81 , d ) 90 , e ) 99

SOLUTION:
c