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: if 20 typists can type 48 letters in 20 minutes , then how many letters will 30 typists working at the same rate complete in 1 hour ? 
Options: a ) 63 , b ) 72 , c ) 144 , d ) 216 , e ) 400

A: d
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Q: Problem: a factory produces 4560 toys per week . if the workers at this factory work 4 days a week and if these workers make the same number of toys everyday , how many toys are produced each day ? 
Options: a ) 1140 toys , b ) 2375 toys , c ) 3375 toys , d ) 4375 toys , e ) 5375 toys

A: a
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Q: Problem: a train running at the speed of 72 km / hr crosses a pole in 9 seconds . find the length of the train . 
Options: a ) 150 meter , b ) 286 meter , c ) 180 meter , d ) 288 meter , e ) 265 meter

A:
c
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