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'.
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Question: Problem: a car ferry can hold up to 70 tons of cargo . what is the greatest number of vehicles that the ferry can carry if half the vehicles are cars with an average ( arithmetic mean ) weight of 0.75 tons and half of the vehicles are trucks with an average ( arithmetic mean ) weight of 4 tons ?
Options: a ) 14 , b ) 20 , c ) 28 , d ) 32 , e ) 36

Answer: c

Question: Problem: if 3 x 5 y = 5 and x / x + y = 5 / 7 , then what is the value of x y ?
Options: a ) 9 , b ) 6 , c ) 4 , d ) 3 , e ) none of these

Answer: d

Question: Problem: sum of 19 odd numbers is ?
Options: a ) 341 , b ) 351 , c ) 361 , d ) 371 , e ) 381

Answer:
c