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

[EX Q]: Problem: it costs $ 6 for the first 1 / 4 hour to use the copier at kinkos . after the first hour it costs $ 8 per hour . if a certain customer uses the copier for 4 hours and 25 minutes , how much will it cost him ?
Options: a ) $ 23.45 , b ) $ 65.33 , c ) $ 40 , d ) $ 38.27 , e ) $ 39.33
[EX A]: e

[EX Q]: Problem: x can finish a work in 25 days . y can finish the same work in 20 days . y worked for 12 days and left the job . how many days does x alone need to finish the remaining work ?
Options: a ) 2 , b ) 5 , c ) 6 , d ) 7 , e ) 8
[EX A]: e

[EX Q]: Problem: while working alone at their constant rates , computer x can process 240 files in 4 hours , and computer y can process 240 files in 6 hours . if all files processed by these computers are the same size , how many hours would it take the two computers , working at the same time at their respective constant rates , to process a total of 240 files ?
Options: a ) 2 , b ) 2.2 , c ) 2.4 , d ) 2.6 , e ) 2.8
[EX A]:
c