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: 0.002 x 0.6 = ? 
Options: a ) 0.0012 , b ) 0.001 , c ) 0.01 , d ) 0.1 , e ) none of these

A: a
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Q: Problem: if a is a positive integer , and if the units digit of a ^ 2 is 9 and the units digit of ( a + 1 ) ^ 2 is 4 , what is the units x digit of ( a + 2 ) ^ 2 ? 
Options: a ) 1 , b ) 3 , c ) 5 , d ) 6 , e ) c . 14

A: a
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Q: Problem: a certain pair of used shoes can be repaired for $ 11.50 and will last for 1 year . a pair of the same kind of shoes can be purchased new for $ 28.00 and will last for 2 years . the average cost per year of the new shoes is what percent greater than the cost of repairing the used shoes ? 
Options: a ) 20.8 , b ) 21.46 , c ) 21.74 , d ) 22.3 , e ) 21.4

A:
c
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