Answer:
See explanation
Step-by-step explanation:
1. Find the GCF of 40 and 44:

So,

2. Find the GCF of 13 and 52:

So,

3. Find the GCF of 15 and 81:

So,

4. Find the GCF of 64 and 28:

So,

Answer:
82
Step-by-step explanation:
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The answer is b because 2-8 is that