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 large field of 900 hectares is divided into two parts . the difference of the areas of the two parts is one - fifth of the average of the two areas . what is the area of the smaller part in hectares ? 
Options: a ) 435 hectares . , b ) 425 hectares . , c ) 445 hectares . , d ) 415 hectares . , e ) 405 hectares .

A: e
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Q: Problem: how many odd 3 - digit integers greater than 800 are there such that all their digits are different ? 
Options: a ) 40 , b ) 56 , c ) 72 , d ) 81 , e ) 104

A: c
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Q: Problem: f ( x ) is a function such that f ( x ) + 3 f ( 8 - x ) = x for all real numbers x . find the value of f ( 2 ) . 
Options: a ) 5 , b ) 4 , c ) 3 , d ) 2 , e ) 1

A:
d
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