The task is to generate the correct answer for a given math problem.

Q: Problem: what is the prime factors ’ number of 18 ?

A: 3
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Q: Problem: lally ' s internet provider offers unlimited traffic which costs $ 0.5 per day charged off at 12 a . m . the service is discontinued when client ' s debt exceeds $ 5 . if today in the morning lally makes a payment of $ 7 , for how many days , including today , will she be connected to the internet without any additional payments , given her initial balance was $ 0 ?

A: 25
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Q: Problem: if x + y = 20 , x - y = 36 , for integers of x and y , x = ?

A:
28
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