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: 120 + 520 ÷ 5.00 = ? 
Options: a ) 100 , b ) 150 , c ) 120 , d ) 520 , e ) none

A: e
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Q: Problem: how many positive integers less than 1000 are multiples of 5 but not of 4 or 7 ? 
Options: a ) 114 , b ) 121 , c ) 122 , d ) 129 , e ) 136

A: c
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Q: Problem: joan took out a mortgage from hel local bank . each monthly mortgage payment she makes must be triple the amount of the previous month ' s payment . if her first payment is $ 100 , and the total amount she must pay back is $ 12100 , how many months will it take joan to pay back her mortgage ? 
Options: a ) 6 , b ) 8 , c ) 10 , d ) 5 , e ) 13

A:
d
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