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: find √ ? / 19 = 4 ? 
Options: a ) 76 , b ) 5776 , c ) 304 , d ) 1296 , e ) none

A: b
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Q: Problem: how many paying stones , each measuring 2 1 / 2 m * 2 m are required to pave a rectangular court yard 20 m long and 16 1 / 2 m board ? 
Options: a ) 66 , b ) 18 , c ) 16 , d ) 10 , e ) 15

A: a
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Q: Problem: the average height of 20 students is 20 cm and the average height of 11 students is 20 cm . what is the average height of the 31 students ? 
Options: a ) 40 cm , b ) 20 cm , c ) 30 cm , d ) 25 cm , e ) 35 cm

A:
b
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