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

Q: Problem: a rower whose speed is 2.5 km / hr in still water rows to a certain point upstream and back to the starting point in a river which flows at 0.5 km / hr . what is the rower ' s average speed ( in km / hr ) for the total journey ? 
Options: a ) 2.2 , b ) 2.3 , c ) 2.4 , d ) 2.5 , e ) 2.6

A: c
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Q: Problem: the average ( arithmetic mean ) of 4 positive integers is 30 . if the average of 2 of these integers is 15 , what is the greatest possible value that one of the other 2 integers can have ? 
Options: a ) 55 , b ) 89 , c ) 100 , d ) 109 , e ) 115

A: b
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Q: Problem: there are 12 students in a class . on the day the test was given , ella was absent . the other 11 students took the test and their average was 74 . the next day , ella took the test , and with this grade included , the new average was 75 . what was ella ' s grade on the test ? 
Options: a ) 82 , b ) 83 , c ) 84 , d ) 85 , e ) 86

A:
e
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