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'.

Q: Problem: ram , who is half as efficient as krish , will take 24 days to complete a task if he worked alone . if ram and krish worked together , how long will they take to complete the task ? 
Options: a ) 16 days , b ) 12 days , c ) 8 days , d ) 6 days , e ) 18 days

A: c
****
Q: Problem: while driving from a - ville to b - town , harriet drove at a constant speed of 105 kilometers per hour . upon arriving in b - town , harriet immediately turned and drove back to a - ville at a constant speed of 145 kilometers per hour . if the entire trip took 5 hours , how many minutes did it take harriet to drive from a - ville to b - town ? 
Options: a ) 138 , b ) 148 , c ) 150 , d ) 162 , e ) 174

A: e
****
Q: Problem: if a takes x days to do a work then b takes 2 x days to do the same work then with in how many day ' s a will alone complete this work ? 
Options: a ) 27 , b ) 23 , c ) 24 , d ) 25 , e ) 26

A:
a
****