Length
5
10
20
30
40
50
100
Open
Level
1
2
3
4
5
6
7
8
9
10
15
20
50
Timer
None
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2:00
3:00
4:00
5:00
10:00
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30:00
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1
2
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4
Animate
No
Yes
Prime numbers
Prime factors
Greatest common factor
Least common multiple
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Factors
2
Prime
OK
Composite
Right
Wrong
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