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1. mineral a scratches minerals e and i, but it can be scratched by mineral j.
2. mineral c can be scratched by every other mineral.
3. mineral e can scratch mineral i.
4. mineral f can scratch only mineral c.
5. mineral b can scratch mineral f, but it can be scratched by all the other minera
6. mineral h can scratch every other mineral.
7. mineral d can be scratched only by mineral h.
8. mineral g can be scratched by minerals hand d; it can scratch mineral j.
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