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 dog is tied to a tree by a long nylon cord . if the dog runs from the due north side of the tree to the due south side of the tree with the cord extended to its full length at all items , and the dog ran approximately 30 feet , what was the approximate length of the nylon cord e , in feet ? 
Options: a ) 30 , b ) 25 , c ) 15 , d ) 10 , e ) 5
d

Problem: a drink vendor has 20 liters of maaza , 144 liters of pepsi and 368 liters of sprite . he wants to pack them in cans , so that each can contains the same number of liters of a drink , and does n ' t want to mix any two drinks in a can . what is the least number of cans required ? 
Options: a ) 135 , b ) 137 , c ) 142 , d ) 130 , e ) 133
e

Problem: if integer k is equal to the sum of all even multiples of 25 between 200 and 600 , what is the greatest prime factor of k ? 
Options: a ) 5 , b ) 7 , c ) 11 , d ) 13 , e ) 17

d