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: a can do a work in 24 days and b can do it in 8 days . in how many days a and b can do the work ? 
Options: a ) 20 days , b ) 10 days , c ) 6 days , d ) 8 days , e ) 7 days

A: c
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Q: Problem: john left home and drove at the rate of 45 mph for 2 hours . he stopped for lunch then drove for another 3 hours at the rate of 45 mph to reach his destination . how many miles did john drive ? 
Options: a ) 235 miles . , b ) 245 miles . , c ) 225 miles . , d ) 265 miles . , e ) 275 miles .

A: c
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Q: Problem: a student reached his school late by 20 mins by travelling at a speed of 9 kmph . if he had travelled at a speed of 12 kmph , he would have reached his school 20 mins early . what is the distance between house and school ? 
Options: a ) 24 , b ) 25 , c ) 26 , d ) 27 , e ) 28

A:
a
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