<span>A. economic fluctuations</span>
<span>Divide by 3 get a remainder of 2
5, 8, 11, 14, 17, 20, ...
Divide by 5 get a remainder of 2
7 , 12, 17, 23, ...
Divide by 7 get a reminder of 5
12, 19, 26, 33, ...
And find a number in all three lists
</span>
<span>Not the most convenient way for sure, but since 47 works it will not take too long</span><span>
</span>
1. 83
2. -37
3. 64
4. 94
5. -85
6. 96
7. -48
8. -92
9. 65
10. 65
11. -32
12. -30