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: 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
[EX A]: c

[EX Q]: Problem: 20 beavers , working together in a constant pace , can build a dam in 18 hours . how many hours will it take 12 beavers that work at the same pace , to build the same dam ? 
Options: a ) 22 . , b ) 24 . , c ) 30 . , d ) 36 , e ) 38 .
[EX A]: c

[EX Q]: Problem: if 3 cm of a pencil is purple , 2 cm of the remaining is black and the remaining 1 cm is blue , what is the total length of the pencil ? 
Options: a ) 6 , b ) 3 , c ) 1 , d ) 4 , e ) 2
[EX A]:
a