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: a rainstorm increased the amount of water stored in state j reservoirs from 124 billion gallons to 140 billion gallons . if the storm increased the amount of water in the reservoirs to 80 percent of total capacity , approximately how many billion gallons of water were the reservoirs short of total capacity prior to the storm ? 
Options: a ) 51 , b ) 48 , c ) 55 , d ) 63 , e ) 65
a

Problem: for any integer k greater than 1 , the symbol k * denotes the product of all integers between 1 and k , inclusive . if k * is a multiple of 315 what is the least possible value of k ? 
Options: a ) 5 , b ) 7 , c ) 9 , d ) 11 , e ) 13
b

Problem: k is a 3 digit number such that the the ratio of the number to the sum of its digits is least . what is the difference between the hundreds and tens digit ? 
Options: a ) 9 , b ) 8 , c ) 7 , d ) 6 , e ) 5

b